0000913760-26-000031 | 10-Q | XBRL Viewer

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Other Expenses (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Other Expenses (Details) - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Other Expenses [Abstract]
Non-income taxes	$ 4.2	$ 2.5	$ 5.1	$ 5.3
Insurance	4.2	2.6	9.0	6.2
Employee related expenses	1.6	1.7	3.7	3.6
Other direct business expenses	8.9	3.9	15.5	7.9
Membership fees	1.4	1.0	2.5	1.9
Director and public company expenses	0.7	0.7	1.2	1.2
Office expenses	1.1	0.6	2.0	1.3
Other expenses	5.7	1.8	15.7	4.1
Total other expenses	$ 27.8	$ 14.8	$ 54.7	$ 31.5

Assets and Liabilities, at Fair Value - Schedule of Financial Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Millions	Mar. 31, 2026	Sep. 30, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 179.8	$ 105.1
Securities and other assets segregated under federal and other regulations	1,117.4	950.0
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	5,307.6	6,442.9
Receivables from clients, net - Derivatives	52.4	58.1
Financial instruments owned	11,261.9	8,604.4
Physical commodities inventory	1,038.8	917.5
Total assets at fair value	18,356.3	16,631.6
Accounts payable and other accrued liabilities - contingent liabilities	59.8
Payables to clients - Derivatives	(41.5)	530.7
Financial instruments sold, not yet purchased	3,789.2	2,919.8
Total liabilities at fair value	3,813.3	3,521.2
To be announced and forward settling securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable to broker-dealers, clearing organizations and counterparties	7.0	49.9
Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable to broker-dealers, clearing organizations and counterparties	(1.2)	(11.5)
Payable to broker-dealers, clearing organizations and counterparties
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable to broker-dealers, clearing organizations and counterparties	5.8	38.4
Contingent Consideration
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Accounts payable and other accrued liabilities - contingent liabilities		32.3
Physical commodities inventory
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Physical commodities inventory	437.2	471.1
Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	715.2	562.7
Financial instruments sold, not yet purchased	479.6	371.7
Corporate and municipal bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	683.6	485.7
Financial instruments sold, not yet purchased	240.4	264.1
U.S. Treasury obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	1,614.6	678.8
Financial instruments sold, not yet purchased	2,626.8	1,983.2
U.S. government agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	912.9	701.9
Financial instruments sold, not yet purchased		1.3
Foreign government obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	2.5	4.1
Agency mortgage-backed obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	6,412.3	5,378.9
Financial instruments sold, not yet purchased	0.1	1.1
Asset-backed obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	185.4	373.4
Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	294.9	190.4
Financial instruments sold, not yet purchased	429.1	297.3
Commodities warehouse receipts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	346.9	144.6
Exchange firm common stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	50.8	47.0
Cash flow hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	2.2	9.5
Financial instruments sold, not yet purchased	11.9	1.0
Mutual funds and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	40.6	27.4
Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments sold, not yet purchased	1.3	0.1
To be announced and forward settling securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	76.5	4.8
Foreign government obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	23.4	21.2
U.S. Treasury obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	2,947.6	5,210.9
U.S. government agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	1,606.9	1,103.1
Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	653.2	102.9
Commodities warehouse receipts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities and other assets segregated under federal and other regulations	21.5	145.4
U.S. government agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities and other assets segregated under federal and other regulations	110.8	110.7
U.S. Treasury obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities and other assets segregated under federal and other regulations	985.1	693.9
Netting
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0.0	0.0
Securities and other assets segregated under federal and other regulations	0.0	0.0
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	(8,091.1)	(6,644.1)
Receivables from clients, net - Derivatives	(1,425.7)	(509.6)
Financial instruments owned	(594.7)	(468.0)
Total assets at fair value	(10,111.5)	(7,621.7)
Accounts payable and other accrued liabilities - contingent liabilities	0.0
Payables to clients - Derivatives	(6,994.2)	(3,486.5)
Financial instruments sold, not yet purchased	(529.8)	(391.6)
Total liabilities at fair value	(10,049.3)	(7,594.3)
Netting \| To be announced and forward settling securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable to broker-dealers, clearing organizations and counterparties	(92.0)	(26.1)
Netting \| Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable to broker-dealers, clearing organizations and counterparties	(2,433.3)	(3,690.1)
Netting \| Payable to broker-dealers, clearing organizations and counterparties
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable to broker-dealers, clearing organizations and counterparties	(2,525.3)	(3,716.2)
Netting \| Contingent Consideration
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Accounts payable and other accrued liabilities - contingent liabilities		0.0
Netting \| Physical commodities inventory
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Physical commodities inventory	0.0	0.0
Netting \| Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased	0.0	0.0
Netting \| Corporate and municipal bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased	0.0	0.0
Netting \| U.S. Treasury obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased	0.0	0.0
Netting \| U.S. government agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased		0.0
Netting \| Foreign government obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Netting \| Agency mortgage-backed obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased	0.0	0.0
Netting \| Asset-backed obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Netting \| Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	(594.7)	(468.0)
Financial instruments sold, not yet purchased	(529.8)	(391.6)
Netting \| Commodities warehouse receipts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Netting \| Exchange firm common stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Netting \| Cash flow hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased	0.0	0.0
Netting \| Mutual funds and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Netting \| Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments sold, not yet purchased	0.0	0.0
Netting \| To be announced and forward settling securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	(91.1)	(30.1)
Netting \| Foreign government obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	0.0	0.0
Netting \| U.S. Treasury obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	0.0	0.0
Netting \| U.S. government agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	0.0	0.0
Netting \| Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	(8,000.0)	(6,614.0)
Netting \| Commodities warehouse receipts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities and other assets segregated under federal and other regulations	0.0	0.0
Netting \| U.S. government agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities and other assets segregated under federal and other regulations	0.0	0.0
Netting \| U.S. Treasury obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities and other assets segregated under federal and other regulations	0.0	0.0
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	179.8	105.1
Securities and other assets segregated under federal and other regulations	1,006.6	839.3
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	9,685.6	8,440.3
Receivables from clients, net - Derivatives	606.9	61.2
Financial instruments owned	2,753.7	1,451.5
Total assets at fair value	14,366.0	11,119.2
Accounts payable and other accrued liabilities - contingent liabilities	0.0
Payables to clients - Derivatives	6,264.6	3,113.1
Financial instruments sold, not yet purchased	3,102.4	2,356.8
Total liabilities at fair value	10,368.0	5,667.4
Level 1 \| To be announced and forward settling securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable to broker-dealers, clearing organizations and counterparties	0.0	0.0
Level 1 \| Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable to broker-dealers, clearing organizations and counterparties	1,001.0	197.5
Level 1 \| Payable to broker-dealers, clearing organizations and counterparties
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable to broker-dealers, clearing organizations and counterparties	1,001.0	197.5
Level 1 \| Contingent Consideration
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Accounts payable and other accrued liabilities - contingent liabilities		0.0
Level 1 \| Physical commodities inventory
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Physical commodities inventory	133.4	221.8
Level 1 \| Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	703.1	556.0
Financial instruments sold, not yet purchased	473.4	367.3
Level 1 \| Corporate and municipal bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased	0.0	0.0
Level 1 \| U.S. Treasury obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	1,614.6	678.8
Financial instruments sold, not yet purchased	2,626.8	1,983.2
Level 1 \| U.S. government agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased		0.0
Level 1 \| Foreign government obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Level 1 \| Agency mortgage-backed obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased	0.0	0.0
Level 1 \| Asset-backed obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Level 1 \| Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased	2.2	6.3
Level 1 \| Commodities warehouse receipts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	346.9	144.6
Level 1 \| Exchange firm common stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	50.8	47.0
Level 1 \| Cash flow hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased	0.0	0.0
Level 1 \| Mutual funds and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	38.3	25.1
Level 1 \| Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments sold, not yet purchased	0.0	0.0
Level 1 \| To be announced and forward settling securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	0.0	0.0
Level 1 \| Foreign government obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	23.4	21.2
Level 1 \| U.S. Treasury obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	2,947.6	5,210.9
Level 1 \| U.S. government agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	0.0	0.0
Level 1 \| Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	6,714.6	3,208.2
Level 1 \| Commodities warehouse receipts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities and other assets segregated under federal and other regulations	21.5	145.4
Level 1 \| U.S. government agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities and other assets segregated under federal and other regulations	0.0	0.0
Level 1 \| U.S. Treasury obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities and other assets segregated under federal and other regulations	985.1	693.9
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0.0	0.0
Securities and other assets segregated under federal and other regulations	110.8	110.7
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	3,713.1	4,646.7
Receivables from clients, net - Derivatives	871.2	506.5
Financial instruments owned	9,100.6	7,618.6
Total assets at fair value	14,099.5	13,131.8
Accounts payable and other accrued liabilities - contingent liabilities	0.0
Payables to clients - Derivatives	688.1	904.1
Financial instruments sold, not yet purchased	1,216.5	954.5
Total liabilities at fair value	3,434.7	5,415.7
Level 2 \| To be announced and forward settling securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable to broker-dealers, clearing organizations and counterparties	99.0	76.0
Level 2 \| Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable to broker-dealers, clearing organizations and counterparties	1,431.1	3,481.1
Level 2 \| Payable to broker-dealers, clearing organizations and counterparties
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable to broker-dealers, clearing organizations and counterparties	1,530.1	3,557.1
Level 2 \| Contingent Consideration
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Accounts payable and other accrued liabilities - contingent liabilities		0.0
Level 2 \| Physical commodities inventory
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Physical commodities inventory	303.8	249.3
Level 2 \| Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	12.1	6.7
Financial instruments sold, not yet purchased	6.2	4.4
Level 2 \| Corporate and municipal bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	683.6	485.7
Financial instruments sold, not yet purchased	240.4	264.1
Level 2 \| U.S. Treasury obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased	0.0	0.0
Level 2 \| U.S. government agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	912.9	701.9
Financial instruments sold, not yet purchased		1.3
Level 2 \| Foreign government obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	2.5	4.1
Level 2 \| Agency mortgage-backed obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	6,412.3	5,378.9
Financial instruments sold, not yet purchased	0.1	1.1
Level 2 \| Asset-backed obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	185.4	373.4
Level 2 \| Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	889.6	658.4
Financial instruments sold, not yet purchased	956.7	682.6
Level 2 \| Commodities warehouse receipts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Level 2 \| Exchange firm common stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Level 2 \| Cash flow hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	2.2	9.5
Financial instruments sold, not yet purchased	11.9	1.0
Level 2 \| Mutual funds and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Level 2 \| Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments sold, not yet purchased	1.2	0.0
Level 2 \| To be announced and forward settling securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	167.6	34.9
Level 2 \| Foreign government obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	0.0	0.0
Level 2 \| U.S. Treasury obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	0.0	0.0
Level 2 \| U.S. government agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	1,606.9	1,103.1
Level 2 \| Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	1,938.6	3,508.7
Level 2 \| Commodities warehouse receipts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities and other assets segregated under federal and other regulations	0.0	0.0
Level 2 \| U.S. government agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities and other assets segregated under federal and other regulations	110.8	110.7
Level 2 \| U.S. Treasury obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities and other assets segregated under federal and other regulations	0.0	0.0
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0.0	0.0
Securities and other assets segregated under federal and other regulations	0.0	0.0
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	0.0	0.0
Receivables from clients, net - Derivatives	0.0
Financial instruments owned	2.3	2.3
Total assets at fair value	2.3	2.3
Accounts payable and other accrued liabilities - contingent liabilities	59.8
Payables to clients - Derivatives	0.0	0.0
Financial instruments sold, not yet purchased	0.1	0.1
Total liabilities at fair value	59.9	32.4
Level 3 \| To be announced and forward settling securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable to broker-dealers, clearing organizations and counterparties	0.0	0.0
Level 3 \| Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable to broker-dealers, clearing organizations and counterparties	0.0	0.0
Level 3 \| Payable to broker-dealers, clearing organizations and counterparties
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payable to broker-dealers, clearing organizations and counterparties	0.0	0.0
Level 3 \| Contingent Consideration
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Accounts payable and other accrued liabilities - contingent liabilities		32.3
Level 3 \| Physical commodities inventory
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Physical commodities inventory	0.0	0.0
Level 3 \| Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased	0.0	0.0
Level 3 \| Corporate and municipal bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased	0.0	0.0
Level 3 \| U.S. Treasury obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased	0.0	0.0
Level 3 \| U.S. government agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased		0.0
Level 3 \| Foreign government obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Level 3 \| Agency mortgage-backed obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased	0.0	0.0
Level 3 \| Asset-backed obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Level 3 \| Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased	0.0	0.0
Level 3 \| Commodities warehouse receipts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Level 3 \| Exchange firm common stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Level 3 \| Cash flow hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	0.0	0.0
Financial instruments sold, not yet purchased	0.0	0.0
Level 3 \| Mutual funds and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	2.3	2.3
Level 3 \| Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments sold, not yet purchased	0.1	0.1
Level 3 \| To be announced and forward settling securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	0.0	0.0
Level 3 \| Foreign government obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	0.0	0.0
Level 3 \| U.S. Treasury obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	0.0	0.0
Level 3 \| U.S. government agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	0.0	0.0
Level 3 \| Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	0.0	0.0
Level 3 \| Commodities warehouse receipts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities and other assets segregated under federal and other regulations	0.0	0.0
Level 3 \| U.S. government agency obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities and other assets segregated under federal and other regulations	0.0	0.0
Level 3 \| U.S. Treasury obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities and other assets segregated under federal and other regulations	0.0	0.0
Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets:	26.7	10.3
Certificates of deposit \| Netting
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets:	0.0	0.0
Certificates of deposit \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets:	26.7	10.3
Certificates of deposit \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets:	0.0	0.0
Certificates of deposit \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets:	0.0	0.0

Basis of Presentation and Consolidation and Accounting Standards Adopted	6 Months Ended
	Mar. 31, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation and Consolidation and Accounting Standards Adopted	Basis of Presentation and Consolidation and Accounting Standards Adopted StoneX Group Inc., a Delaware corporation, and its consolidated subsidiaries (collectively “StoneX” or “the Company”), is a global financial services network that connects companies, organizations, traders and investors to the global market ecosystem through a unique blend of digital platforms, end-to-end clearing and execution services, high touch service, and deep expertise. The Company’s common stock trades on The NASDAQ Global Select Market under the symbol “SNEX”. Basis of Presentation The accompanying unaudited Condensed Consolidated Balance Sheet as of September 30, 2025, which has been derived from the audited consolidated balance sheet as of September 30, 2025, and the unaudited interim condensed consolidated financial statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and disclosures normally included in annual consolidated financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) have been condensed or omitted pursuant to those rules and regulations. The Company believes that the included disclosures clearly and fairly present the information within. In management’s opinion, all adjustments, generally consisting of normal accruals, considered necessary to fairly present the condensed consolidated financial statements for the interim periods presented have been reflected as required by Rule 10-01 of Regulation S-X. Operating results for interim periods are not necessarily indicative of the results that may be expected for the full year. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and related notes contained in the Company’s Annual Report on Form 10-K for the fiscal year ended September 30, 2025, as filed with the SEC. These condensed consolidated financial statements include the accounts of StoneX Group Inc. and all entities in which the Company has a controlling financial interest. All material intercompany transactions and balances have been eliminated in consolidation. Preparing condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent liabilities as of the date of the condensed consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. The most significant of these estimates and assumptions in the current year relate to fair value measurements for financial instruments, revenue recognition, valuation of inventories, and income taxes. The Company reviews all significant estimates affecting the financial statements on a recurring basis and makes necessary adjustments to the financial statements presented within this Form 10-Q. Although these and other estimates and assumptions are based on the best available information, actual results could be materially different from estimates. Estimates and assumptions are based on management’s best knowledge of current events and actions the Company may undertake in the future, using information reasonably available to the Company as of March 31, 2026 and through the date of this Form 10-Q. Common Stock Split On February 3, 2026, the Company’s Board of Directors approved a 3-for-2 split of its common stock, effected as a stock dividend entitling each shareholder of record to receive one additional share of common stock for every two shares owned. Additional shares issued as a result of the stock dividend were distributed after close of trading on March 20, 2026, to stockholders of record at the close of business on March 10, 2026. Cash was distributed in lieu of fractional shares based on the opening price of a share of common stock on March 11, 2026. All share and per share amounts contained herein have been retroactively adjusted for this stock split. The shares of common stock retain a par value of $0.01 per share. Accordingly, an amount equal to the par value of the increased shares resulting from the stock split was reclassified from Additional paid-in-capital to Common stock. Accounting Standards Adopted In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2023-07, Improvements to Reportable Segment Disclosures, which requires entities to enhance disclosures regarding segments, including significant segment expenses. The Company adopted ASU No. 2023-07 related to annual disclosure requirements effective with the fiscal 2025 Form 10-K, with newly required annual disclosures being included in Note 22 of the fiscal 2025 Form 10-K. The Company adopted ASU 2023-07 related to interim disclosure requirements effective with the first quarter fiscal 2026 10-Q filing and applied the updated disclosure requirements retrospectively to all periods presented. See Note 18 for more information.

Condensed Consolidated Statements of Stockholders’ Equity (Unaudited) - USD ($) $ in Millions	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss, net
Beginning balance at Sep. 30, 2024	$ 1,709.1	$ 0.8	$ (69.3)	$ 413.9	$ 1,388.9	$ (25.2)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	156.8				156.8
Other comprehensive gain (loss), net of tax	(6.6)					(6.6)
Exercise of stock options	4.8			4.8
Shares withheld to cover taxes on vesting of equity awards	(4.1)			(4.1)
Share-based compensation	22.0			22.0
Ending balance at Mar. 31, 2025	1,882.0	0.8	(69.3)	436.6	1,545.7	(31.8)
Beginning balance at Dec. 31, 2024	1,777.4	0.8	(69.3)	422.3	1,474.0	(50.4)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	71.7				71.7
Other comprehensive gain (loss), net of tax	18.6					18.6
Exercise of stock options	4.0			4.0
Shares withheld to cover taxes on vesting of equity awards	(0.4)			(0.4)
Share-based compensation	10.7			10.7
Ending balance at Mar. 31, 2025	1,882.0	0.8	(69.3)	436.6	1,545.7	(31.8)
Beginning balance at Sep. 30, 2025	2,377.4	0.8	(32.8)	730.6	1,694.8	(16.0)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	313.3				313.3
Other comprehensive gain (loss), net of tax	(18.1)					(18.1)
Exercise of stock options	8.6			8.6
Shares withheld to cover taxes on vesting of equity awards	(9.9)			(9.9)
Share-based compensation	28.0			28.0
Ending balance at Mar. 31, 2026	2,699.3	0.8	(32.8)	757.3	2,008.1	(34.1)
Beginning balance at Dec. 31, 2025	2,522.2	0.8	(32.8)	739.6	1,833.8	(19.2)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	174.3				174.3
Other comprehensive gain (loss), net of tax	(14.9)					(14.9)
Exercise of stock options	7.7			7.7
Shares withheld to cover taxes on vesting of equity awards	(3.7)			(3.7)
Share-based compensation	13.7			13.7
Ending balance at Mar. 31, 2026	$ 2,699.3	$ 0.8	$ (32.8)	$ 757.3	$ 2,008.1	$ (34.1)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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- Definition

Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest.

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+ Details

Credit Facilities - Narrative (Details) - USD ($)		6 Months Ended
Credit Facilities - Narrative (Details) - USD ($)	Dec. 01, 2025	Mar. 31, 2026	Mar. 31, 2025	Jul. 08, 2025	Mar. 01, 2024
Line of Credit Facility [Line Items]
Repayments of note payable	$ 6,300,000	$ 6,300,000	$ 0
Subordinated Credit Facility \| Line of Credit \| R.J. O’Brien
Line of Credit Facility [Line Items]
Total Commitment		$ 180,000,000.0
Senior Secured Notes due 2031 \| Senior Notes
Line of Credit Facility [Line Items]
Debt instrument, face amount					$ 550,000,000.0
Debt instrument, interest rate, stated percentage		7.875%
Debt instrument offering price, percentage					100.00%
Debt issuance costs, gross					$ 7,700,000
Senior Secured Notes due 2032 \| Senior Notes
Line of Credit Facility [Line Items]
Debt instrument, face amount				$ 625,000,000.0
Debt instrument, interest rate, stated percentage		6.875%		6.875%
Debt instrument offering price, percentage				100.00%
Debt issuance costs, gross				$ 10,500,000
Revolving Credit Facility \| Committed Credit Facilities
Line of Credit Facility [Line Items]
Total Commitment		$ 1,685,000,000

Accumulated Other Comprehensive Loss, Net (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 2,522.2	$ 1,777.4	$ 2,377.4	$ 1,709.1
Other comprehensive loss, net of tax	(14.9)	18.6	(18.1)	(6.6)
Ending balance	2,699.3	1,882.0	2,699.3	1,882.0
Foreign Currency Translation Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(21.4)
Other comprehensive loss, net of tax			0.1
Ending balance	(21.3)		(21.3)
Pension Benefits Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(1.3)
Other comprehensive loss, net of tax			0.0
Ending balance	(1.3)		(1.3)
Cash Flow Hedge
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			6.7
Other comprehensive loss, net of tax			(18.2)
Ending balance	(11.5)		(11.5)
Accumulated Other Comprehensive Loss, net
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(19.2)	(50.4)	(16.0)	(25.2)
Other comprehensive loss, net of tax	(14.9)	18.6	(18.1)	(6.6)
Ending balance	$ (34.1)	$ (31.8)	$ (34.1)	$ (31.8)

- Definition

Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest.

+ References

+ Details

Regulatory Capital Requirements - Schedule of Subsidiaries with Minimum Regulatory Requirements (Details) $ in Millions	Mar. 31, 2026 USD ($)
Capital and Other Regulatory Requirements [Abstract]
Adjusted net capital	$ 10.0
StoneX Financial Inc.
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Actual	536.4
Minimum Requirement	359.2
StoneX Financial Ltd.
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Actual	603.6
Minimum Requirement	437.1
Gain Capital Group, LLC
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Actual	80.9
Minimum Requirement	30.0
StoneX Financial Pte. Ltd.
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Actual	144.8
Minimum Requirement	40.1
StoneX Markets LLC
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Actual	261.5
Minimum Requirement	166.4
R.J. O'Brien & Associates, LLC
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Actual	450.9
Minimum Requirement	$ 341.2

Assets and Liabilities, at Fair Value - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2026	Sep. 30, 2025	Jul. 08, 2025
Senior Secured Notes due 2031
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying value	$ 544.7	$ 544.1
Senior Secured Notes due 2031 \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument, interest rate, stated percentage	7.875%
Senior Secured Notes due 2031 \| Senior Notes \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	$ 570.9
Senior Secured Notes due 2032
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying value	$ 615.6	$ 614.9
Senior Secured Notes due 2032 \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument, interest rate, stated percentage	6.875%		6.875%
Senior Secured Notes due 2032 \| Senior Notes \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	$ 630.7

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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+ Details

Physical Commodities Inventory

6 Months Ended

Mar. 31, 2026

Inventory Disclosure [Abstract]

Physical Commodities Inventory

The Company’s inventories consist of physical commodities as shown below:


(in millions)	March 31, 2026		September 30, 2025
Physical Agriculture and Energy	$	303.8	$	249.3
Precious metals - held by broker-dealer subsidiary	133.4		221.8
Precious metals - held by non-broker-dealer subsidiaries(1)	601.6		446.4
Physical commodities inventory, net	$	1,038.8	$	917.5
(1)Includes raw materials of $2.4 million and work in process of $148.4 million as of March 31, 2026

Physical Agriculture and Energy consists of agricultural commodity inventories, including corn, soybeans, wheat, dried distillers grain, canola, sorghum, coffee, cocoa, cotton, and various energy commodity inventories. Agricultural inventories have reliable, readily determinable and realizable market prices, have relatively insignificant costs of disposal and are available for immediate delivery. The Company records changes to these values in Cost of sales of physical commodities on the Condensed Consolidated Income Statements.

Acquisitions

6 Months Ended

Mar. 31, 2026

Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract]

Acquisitions

The Company’s condensed consolidated financial statements include the operating results and cash flows of the acquired businesses from the dates of acquisition.

Current Year Acquisitions

WCS International Limited

On March 23, 2026, the Company’s wholly owned subsidiary, StoneX Financial Ltd., completed the acquisition of WCS International Limited (“WCSI”), a London based wholesale banknotes trading and distribution business. The acquisition enhances the Company’s relevance to financial institutions by adding a complementary product and capability alongside the existing cross-border payments business.

The purchase price consists of $8.6 million of cash consideration paid at closing and deferred consideration totaling $4.2 million. The business activities of WCSI have been assigned to the Company’s Payments reportable segment. The acquisition generated $8.0 million of Goodwill.

Intercam Advisors, Inc. and Intercam Securities, Inc.

On October 17, 2025, the Company completed the acquisition of Intercam Advisors, Inc. and Intercam Securities, Inc. (together “Intercam”), both U.S.-based firms providing brokerage and investment advisory services to Latin American clients. This acquisition bolsters the Company’s existing wealth management business and further strengthens its connection with Latin America. Through this transaction, the Company expands its ability to serve cross-border clients with a broader range of integrated advisory and brokerage solutions supported by the firm’s global reach and infrastructure.

The purchase price consists of $1.7 million of cash consideration paid at closing and deferred consideration totaling $0.8 million. The business activities of Intercam have been assigned to the Company’s Self-Directed/Retail reportable segment. The acquisition generated $0.4 million of Goodwill.

Plantureux et Associés

On October 31, 2025, the Company’s wholly owned subsidiary, StoneX Financial Europe GmbH, completed the acquisition of Plantureux et Associés (“Plantureux”), a Paris-based brokerage firm specializing in agricultural commodities across both the physical and derivatives markets. The acquisition provides a strategic foothold in the French agricultural commodities market – Europe’s leading grain producing region. With nearly 40 years of experience in agricultural commodities, Plantureux is a respected intermediary in the French cereal market, known for its deep knowledge of the industry and its strong relationships with both buyers and sellers.

The purchase price consists of $2.8 million of cash consideration paid at closing and deferred consideration totaling $1.2 million. The business activities of Plantureux have been assigned to the Company’s Commercial reportable segment. The acquisition generated $2.9 million of Goodwill.

The Assets of GEA Capital

On October 7, 2025, the Company acquired certain assets of GEA Capital (“GEA”) to add to the Company’s Independent Wealth businesses by delivering boutique-style services to both private and corporate clients. The purchase price consists of $5.2 million of cash consideration paid at closing and deferred consideration totaling $16.5 million. The acquired asset was a customer list asset valued at $21.7 million.

Prior Year Acquisitions

R.J. O’Brien

On April 14, 2025, the Company announced that it had entered into a definitive agreement with RTS Merger Sub Inc., RTS Investor Corp., and Westmoor Trail Partners LLC to acquire 100% ownership of RTS Investor Corp., which was the parent company for the R.J. O’Brien global business (“RJO”), including R.J. O’Brien & Associates, LLC, the oldest futures brokerage in the U.S., and selected affiliates. This transaction was effective on the closing date of July 31, 2025.

The aggregate merger consideration was (in millions):


Cash consideration	$	651.9
Common stock	300.1
Amounts receivable from sellers	(10.0)
Total merger consideration	$	942.0

Total fair value of intangible assets acquired	$	410.6
Goodwill(1)	$	166.6
(1) The current period contains a reduction of Goodwill of $7.8 million, related to changes to the estimated fair value of acquired assets and liabilities

Post-Acquisition Results and Unaudited Pro Forma Information

RJO’s results of operations and cash flows have been included in the Company’s condensed consolidated financial statements for the period subsequent to July 31, 2025. As of March 31, 2026 the Company’s fair value and purchase price accounting are preliminary.

For the three and six months ended March 31, 2026, the Company’s results include total operating revenues and net income from RJO, as follows (in millions):


	Three Months Ended March 31, 2026		Six Months Ended March 31, 2026
Operating revenue	$	213.5	$	414.5
Net income	$	20.9	$	40.3

The following unaudited pro forma financial information (in millions, except per share amounts) has been adjusted to give effect to the RJO merger as if it had been consummated on October 1, 2024. The pro forma adjustments include additional interest expense related to the Notes Due 2032, net of tax and intangible amortization, net of tax. RJO net income included an unrealized mark to market gain of $14.2 million and a loss of $4.0 million on RJO’s investment portfolio for the three and six months ended March 31, 2025, respectively.


	Three Months Ended March 31, 2025		Six Months Ended March 31, 2025
Total revenues	$	37,114.2	$	65,258.6
Operating revenues	$	1,179.5	$	2,332.9
Net income	$	94.4	$	173.9
Basic earnings per share	$	1.23	$	2.27
Diluted earnings per share	$	1.17	$	2.16

- Definition

The entire disclosure for business combination.

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-URI https://asc.fasb.org/1943274/2147479328/805-10-50-2

Reference 20: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479328/805-10-50-4

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479581/805-30-50-4

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479907/805-20-50-1

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479907/805-20-50-1

Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(4)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479328/805-10-50-2

Reference 25: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
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-Subparagraph (e)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479328/805-10-50-2

Reference 26: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 40
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479326/805-40-45-1

Reference 27: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/805-30/tableOfContent

Reference 28: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/805-20/tableOfContent

Reference 29: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479328/805-10-50-7

Reference 30: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479328/805-10-50-5

Reference 31: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/805-10/tableOfContent

+ Details

Assets and Liabilities, at Fair Value (Tables)

6 Months Ended

Mar. 31, 2026

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Assets Measured on Recurring Basis

The following tables set forth the Company’s financial and nonfinancial assets and liabilities accounted for at fair value, on a recurring basis, as of March 31, 2026 and September 30, 2025 by level in the fair value hierarchy. All fair value measurements were performed on a recurring basis as of March 31, 2026 and September 30, 2025.


	March 31, 2026
(in millions)	Level 1		Level 2		Level 3		Netting (1)		Total
Assets:
Certificates of deposit	$	26.7	$	—	$	—	$	—	$	26.7
Money market mutual funds and other	153.1		—		—		—		153.1
Cash and cash equivalents	179.8		—		—		—		179.8
Commodities warehouse receipts	21.5		—		—		—		21.5
U.S. government agency obligations	—		110.8		—		—		110.8
U.S. Treasury obligations	985.1		—		—		—		985.1
Securities and other assets segregated under federal and other regulations	1,006.6		110.8		—		—		1,117.4
U.S. Treasury obligations	2,947.6		—		—		—		2,947.6
U.S. government agency obligations	—		1,606.9		—		—		1,606.9
To be announced and forward settling securities	—		167.6		—		(91.1)		76.5
Foreign government obligations	23.4		—		—		—		23.4
Derivatives	6,714.6		1,938.6		—		(8,000.0)		653.2
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	9,685.6		3,713.1		—		(8,091.1)		5,307.6
Receivables from clients, net - Derivatives	606.9		871.2		—		(1,425.7)		52.4
Equity securities	703.1		12.1		—		—		715.2
Corporate and municipal bonds	—		683.6		—		—		683.6
U.S. Treasury obligations	1,614.6		—		—		—		1,614.6
U.S. government agency obligations	—		912.9		—		—		912.9
Foreign government obligations	—		2.5		—		—		2.5
Agency mortgage-backed obligations	—		6,412.3		—		—		6,412.3
Asset-backed obligations	—		185.4		—		—		185.4
Derivatives	—		889.6		—		(594.7)		294.9

Commodities warehouse receipts	346.9		—		—		—		346.9
Exchange firm common stock	50.8		—		—		—		50.8
Cash flow hedges	—		2.2		—		—		2.2
Mutual funds and other	38.3		—		2.3		—		40.6
Financial instruments owned	2,753.7		9,100.6		2.3		(594.7)		11,261.9
Physical commodities inventory	133.4		303.8		—		—		437.2
Total assets at fair value	$	14,366.0	$	14,099.5	$	2.3	$	(10,111.5)	$	18,356.3
Liabilities:
Accounts payable and other accrued liabilities - contingent liabilities	$	—	$	—	$	59.8	$	—	$	59.8
Payables to clients - Derivatives	6,264.6		688.1		—		(6,994.2)		(41.5)
To be announced and forward settling securities	—		99.0		—		(92.0)		7.0
Derivatives	1,001.0		1,431.1		—		(2,433.3)		(1.2)
Payable to broker-dealers, clearing organizations and counterparties	1,001.0		1,530.1		—		(2,525.3)		5.8
Equity securities	473.4		6.2		—		—		479.6

Corporate and municipal bonds	—		240.4		—		—		240.4
U.S. Treasury obligations	2,626.8		—		—		—		2,626.8

Agency mortgage-backed obligations	—		0.1		—		—		0.1

Derivatives	2.2		956.7		—		(529.8)		429.1
Cash flow hedges	—		11.9		—		—		11.9

Other	—		1.2		0.1		—		1.3
Financial instruments sold, not yet purchased	3,102.4		1,216.5		0.1		(529.8)		3,789.2
Total liabilities at fair value	$	10,368.0	$	3,434.7	$	59.9	$	(10,049.3)	$	3,813.3

(1)Represents cash collateral and the impact of netting across each level of the fair value hierarchy.


	September 30, 2025
(in millions)	Level 1		Level 2		Level 3		Netting (1)		Total
Assets:
Certificates of deposit	$	10.3	$	—	$	—	$	—	$	10.3
Money market mutual funds	94.8		—		—		—		94.8
Cash and cash equivalents	105.1		—		—		—		105.1
Commodities warehouse receipts	145.4		—		—		—		145.4
U.S. government agency obligations	—		110.7		—		—		110.7
U.S. Treasury obligations	693.9		—		—		—		693.9
Securities and other assets segregated under federal and other regulations	839.3		110.7		—		—		950.0
U.S. Treasury obligations	5,210.9		—		—		—		5,210.9
U.S. government agency obligations	—		1,103.1		—		—		1,103.1
To be announced and forward settling securities	—		34.9		—		(30.1)		4.8
Foreign government obligations	21.2		—		—		—		21.2
Derivatives	3,208.2		3,508.7		—		(6,614.0)		102.9
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	8,440.3		4,646.7		—		(6,644.1)		6,442.9
Receivables from clients, net - Derivatives	61.2		506.5				(509.6)		58.1
Equity securities	556.0		6.7		—		—		562.7
Corporate and municipal bonds	—		485.7		—		—		485.7
U.S. Treasury obligations	678.8		—		—		—		678.8
U.S. government agency obligations	—		701.9		—		—		701.9
Foreign government obligations	—		4.1		—		—		4.1
Agency mortgage-backed obligations	—		5,378.9		—		—		5,378.9
Asset-backed obligations	—		373.4		—		—		373.4
Derivatives	—		658.4		—		(468.0)		190.4

Commodities warehouse receipts	144.6		—		—		—		144.6
Exchange firm common stock	47.0		—		—		—		47.0
Cash flow hedges	—		9.5		—		—		9.5
Mutual funds and other	25.1		—		2.3		—		27.4

Financial instruments owned	1,451.5		7,618.6		2.3		(468.0)		8,604.4
Physical commodities inventory	221.8		249.3		—		—		471.1
Total assets at fair value	$	11,119.2	$	13,131.8	$	2.3	$	(7,621.7)	$	16,631.6
Liabilities:
Accounts payable and other accrued liabilities - contingent liabilities	$	—	$	—	$	32.3	$	—	$	32.3
Payables to clients - Derivatives	3,113.1		904.1		—		(3,486.5)		530.7
To be announced and forward settling securities	—		76.0		—		(26.1)		49.9
Derivatives	197.5		3,481.1		—		(3,690.1)		(11.5)
Payable to broker-dealers, clearing organizations and counterparties	197.5		3,557.1		—		(3,716.2)		38.4
Equity securities	367.3		4.4		—		—		371.7

Corporate and municipal bonds	—		264.1		—		—		264.1
U.S. Treasury obligations	1,983.2		—		—		—		1,983.2
U.S. government agency obligations	—		1.3		—		—		1.3
Agency mortgage-backed obligations	—		1.1		—		—		1.1

Derivatives	6.3		682.6		—		(391.6)		297.3
Cash flow hedges	—		1.0		—		—		1.0
Other	—		—		0.1		—		0.1

Financial instruments sold, not yet purchased	2,356.8		954.5		0.1		(391.6)		2,919.8
Total liabilities at fair value	$	5,667.4	$	5,415.7	$	32.4	$	(7,594.3)	$	3,521.2

(1)Represents cash collateral and the impact of netting across each level of the fair value hierarchy.

Segment Analysis (Tables)

6 Months Ended

Mar. 31, 2026

Segment Reporting [Abstract]

Schedule of Segment Reporting Information

Information for the reportable segments is shown in accordance with the Segment Reporting Topic of the ASC as follows:


	Three Months Ended March 31, 2026
(in millions)	Commercial		Institutional		Self-Directed / Retail		Payments		Corporate		Eliminations		Total
Non-interest revenues	$	44,646.1	$	372.6	$	98.7	$	55.7	$	10.9	$	(0.9)	$	45,183.1
Interest income	85.7		495.8		7.8		0.3		8.8		(20.6)		577.8
Total revenues	44,731.8		868.4		106.5		56.0		19.7		(21.5)		45,760.9
Cost of sales of physical commodities	44,194.2		—		—		—		(0.1)		—		44,194.1
Operating revenues	537.6		868.4		106.5		56.0		19.8		(21.5)		1,566.8
Transaction-based clearing expenses	41.9		102.3		4.5		2.2		2.7		(0.9)		152.7
Introducing broker commissions	51.7		17.0		27.4		1.3		—		—		97.4
Total interest expense	33.8		433.6		2.2		—		38.6		(20.6)		487.6
Net operating revenues	410.2		315.5		72.4		52.5		(21.5)		—		829.1
Variable compensation and benefits	95.1		114.2		4.3		8.8		26.1		—		248.5
Net contribution	315.1		201.3		68.1		43.7		(47.6)		—		580.6
Fixed compensation and benefits	24.5		36.7		8.6		5.3		83.6		—		158.7
Trading systems and market information	5.5		10.3		3.2		0.2		6.6		—		25.8
Professional fees	1.6		3.0		1.5		1.0		11.3		—		18.4
Non-trading technology and support	0.6		1.2		2.1		0.4		24.1		—		28.4
Selling and marketing	1.8		1.2		8.6		0.1		2.3		—		14.0
Travel and business development	2.7		2.8		0.5		0.2		10.6		—		16.8
Depreciation and amortization	6.1		5.5		3.8		1.3		10.2		—		26.9
Bad debts, net of recoveries	10.4		1.5		0.5		—		—		—		12.4
Shared services	11.8		7.0		3.7		2.5		(25.0)		—		—
Other fixed expenses	5.8		8.7		5.4		0.7		28.8		—		49.4
Non-variable expenses	70.8		77.9		37.9		11.7		152.5		—		350.8
Other losses	—		(2.5)		—		(0.2)		—		—		(2.7)
Segment income	$	244.3	$	120.9	$	30.2	$	31.8	$	(200.1)	$	—	$	227.1


	Three Months Ended March 31, 2025
(in millions)	Commercial		Institutional		Self-Directed / Retail		Payments		Corporate		Eliminations		Total
Non-interest revenues	$	36,138.4	$	223.8	$	84.6	$	49.8	$	5.9	$	(0.8)	$	36,501.7
Interest income	46.1		337.4		7.6		0.5		10.8		(13.4)		389.0
Total revenues	36,184.5		561.2		92.2		50.3		16.7		(14.2)		36,890.7
Cost of sales of physical commodities	35,934.7		—		—		—		—		—		35,934.7
Operating revenues	249.8		561.2		92.2		50.3		16.7		(14.2)		956.0
Transaction-based clearing expenses	19.1		67.1		3.2		1.7		1.5		(0.8)		91.8
Introducing broker commissions	13.1		7.2		24.2		1.0		—		—		45.5
Total interest expense	23.3		295.9		1.8		—		23.8		(13.4)		331.4
Net operating revenues	194.3		191.0		63.0		47.6		(8.6)		—		487.3
Variable compensation and benefits	53.4		62.5		4.6		8.8		17.4		—		146.7
Net contribution	140.9		128.5		58.4		38.8		(26.0)		—		340.6
Fixed compensation and benefits	19.8		21.8		8.8		7.4		62.6		—		120.4
Trading systems and market information	4.7		7.7		3.3		0.3		3.5		—		19.5
Professional fees	1.9		1.9		2.8		1.2		8.7		—		16.5
Non-trading technology and support	0.4		1.0		2.6		0.5		16.4		—		20.9
Selling and marketing	1.2		0.8		8.9		0.2		2.3		—		13.4
Travel and business development	2.0		1.9		0.5		0.3		2.4		—		7.1
Depreciation and amortization	2.1		1.0		4.3		1.2		7.0		—		15.6
Bad debts, net of recoveries	(0.3)		(0.1)		0.6		(0.1)		—		—		0.1
Shared services	7.0		3.5		2.3		2.1		(14.9)		—		—
Other fixed expenses	4.9		2.5		2.8		1.2		18.6		—		30.0
Non-variable expenses	43.7		42.0		36.9		14.3		106.6		—		243.5

Segment income	$	97.2	$	86.5	$	21.5	$	24.5	$	(132.6)	$	—	$	97.1


	Six Months Ended March 31, 2026
(in millions)	Commercial		Institutional		Self-Directed / Retail		Payments		Corporate		Eliminations		Total
Non-interest revenues	$	82,585.2	$	737.3	$	185.6	$	112.4	$	13.0	$	(1.7)	$	83,631.8
Interest income	165.6		997.1		15.3		0.6		18.9		(38.5)		1,159.0
Total revenues	82,750.8		1,734.4		200.9		113.0		31.9		(40.2)		84,790.8
Cost of sales of physical commodities	81,785.8		—		—		—		—		—		81,785.8
Operating revenues	965.0		1,734.4		200.9		113.0		31.9		(40.2)		3,005.0
Transaction-based clearing expenses	72.2		197.6		8.1		4.2		4.9		(1.7)		285.3
Introducing broker commissions	101.6		31.7		54.8		2.3		0.2		—		190.6
Total interest expense	64.7		865.4		4.3		—		79.7		(38.5)		975.6
Net operating revenues	726.5		639.7		133.7		106.5		(52.9)		—		1,553.5
Variable compensation and benefits	176.2		221.5		9.4		17.4		39.9		—		464.4
Net contribution	550.3		418.2		124.3		89.1		(92.8)		—		1,089.1
Fixed compensation and benefits	47.0		63.1		15.9		10.2		162.5		—		298.7
Trading systems and market information	10.2		21.8		6.1		0.4		12.3		—		50.8
Professional fees	4.0		18.2		3.4		1.4		24.2		—		51.2
Non-trading technology and support	1.1		2.7		3.7		0.7		46.8		—		55.0
Selling and marketing	2.6		2.5		16.9		0.2		5.9		—		28.1
Travel and business development	5.9		6.1		1.0		0.5		15.1		—		28.6
Depreciation and amortization	11.6		10.9		6.8		2.6		20.0		—		51.9
Bad debts, net of recoveries	11.4		1.6		0.6		—		—		—		13.6
Shared services	21.1		13.7		6.9		5.4		(47.1)		—		—
Other fixed expenses	12.0		14.9		14.5		1.4		53.3		—		96.1
Non-variable expenses	126.9		155.5		75.8		22.8		293.0		—		674.0
Other losses	—		(2.5)		—		(0.6)		—		—		(3.1)
Segment income	$	423.4	$	260.2	$	48.5	$	65.7	$	(385.8)	$	—	$	412.0

	As of March 31, 2026
Total assets	$	10,896.2	$	38,787.2	$	1,342.2	$	606.1	$	1,995.2	$	—	$	53,626.9


	Six Months Ended March 31, 2025
(in millions)	Commercial		Institutional		Self-Directed / Retail		Payments		Corporate		Eliminations		Total
Non-interest revenues	$	63,310.9	$	438.4	$	197.9	$	107.3	$	5.9	$	(1.6)	$	64,058.8
Interest income	99.4		662.4		15.9		1.1		21.9		(33.5)		767.2
Total revenues	63,410.3		1,100.8		213.8		108.4		27.8		(35.1)		64,826.0
Cost of sales of physical commodities	62,925.7		—		—		—		—		—		62,925.7
Operating revenues	484.6		1,100.8		213.8		108.4		27.8		(35.1)		1,900.3
Transaction-based clearing expenses	36.7		130.1		6.6		3.5		3.0		(1.6)		178.3
Introducing broker commissions	24.4		15.3		48.2		1.9		—		—		89.8
Total interest expense	37.7		590.4		3.7		—		54.5		(33.5)		652.8
Net operating revenues	385.8		365.0		155.3		103.0		(29.7)		—		979.4
Variable compensation and benefits	97.1		118.7		7.4		17.9		38.9		—		280.0
Net contribution	288.7		246.3		147.9		85.1		(68.6)		—		699.4
Fixed compensation and benefits	36.9		40.4		18.1		14.0		130.2		—		239.6
Trading systems and market information	8.7		15.6		6.8		0.7		7.7		—		39.5
Professional fees	4.0		6.6		5.4		1.9		17.6		—		35.5
Non-trading technology and support	0.8		1.9		4.7		1.0		32.2		—		40.6
Selling and marketing	2.5		1.8		17.6		0.3		3.2		—		25.4
Travel and business development	4.3		4.3		1.1		0.6		5.2		—		15.5
Depreciation and amortization	3.9		2.0		9.6		2.2		13.6		—		31.3
Bad debts, net of recoveries	0.9		(0.1)		1.1		—		—		—		1.9
Shared services	13.8		6.9		5.4		4.2		(30.3)		—		—
Other fixed expenses	11.6		3.6		6.0		1.6		39.0		—		61.8
Non-variable expenses	87.4		83.0		75.8		26.5		218.4		—		491.1
Other gains, net	—		1.3		4.4		—		—		—		5.7
Segment income	$	201.3	$	164.6	$	76.5	$	58.6	$	(287.0)	$	—	$	214.0

	As of September 30, 2025
Total assets	$	9,826.3	$	32,465.5	$	1,256.2	$	722.5	$	997.5	$	—	$	45,268.0

Intangible Assets (Tables)

6 Months Ended

Mar. 31, 2026

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Finite and Indefinite-Lived Intangible Assets

The gross and net carrying values of intangible assets as of the balance sheet dates, by major intangible asset class are as follows (in millions):


	March 31, 2026						September 30, 2025
	Gross Amount		Accumulated Amortization		Net Amount		Gross Amount		Accumulated Amortization		Net Amount
Intangible assets subject to amortization
Trade/domain names and other licenses	$	7.1	$	(3.4)	$	3.7	$	10.6	$	(4.9)	$	5.7
Software programs/platforms	2.4		(2.2)		0.2		2.4		(2.0)		0.4
Client and supplier base	465.9		(33.7)		432.2		445.0		(19.2)		425.8
Total intangible assets subject to amortization	475.4		(39.3)		436.1		458.0		(26.1)		431.9

Intangible assets not subject to amortization
Website domains	2.2		—		2.2		2.3		—		2.3
Business licenses	3.7		—		3.7		3.7		—		3.7
Total intangible assets not subject to amortization	5.9		—		5.9		6.0		—		6.0
Total intangible assets	$	481.3	$	(39.3)	$	442.0	$	464.0	$	(26.1)	$	437.9

Schedule of Expected Amortization Expense

As of March 31, 2026, estimated future amortization expense was as follows:


(in millions)
Fiscal 2026 (remaining months)	$	16.7
Fiscal 2027	31.1
Fiscal 2028	30.0
Fiscal 2029	29.2
Fiscal 2030 and thereafter	329.1
Total intangible assets subject to amortization	$	436.1

Other Expenses (Tables)

6 Months Ended

Mar. 31, 2026

Other Expenses [Abstract]

Schedule of Other Operating Cost and Expense, by Component

Other expenses consisted of the following, for the periods indicated.


	Three Months Ended March 31,				Six Months Ended March 31,
(in millions)	2026		2025		2026		2025
Non-income taxes	$	4.2	$	2.5	$	5.1	$	5.3
Insurance	4.2		2.6		9.0		6.2
Employee related expenses	1.6		1.7		3.7		3.6
Other direct business expenses	8.9		3.9		15.5		7.9
Membership fees	1.4		1.0		2.5		1.9
Director and public company expenses	0.7		0.7		1.2		1.2
Office expenses	1.1		0.6		2.0		1.3
Other expenses	5.7		1.8		15.7		4.1
Total other expenses	$	27.8	$	14.8	$	54.7	$	31.5

Securities and Commodity Financing Transactions (Tables)

6 Months Ended

Mar. 31, 2026

Broker-Dealer [Abstract]

Schedule of Underlying Assets of Repurchase Agreements when Amount of Repurchase Agreements Exceeds 10 Percent of Assets

The following tables set forth the carrying value of repurchase agreements, and securities lending agreements by remaining contractual maturity (in millions):


	March 31, 2026
	Overnight and Open		Less than 30 Days		30-90 Days		Over 90 Days		Total
Securities sold under agreements to repurchase	$	30,726.8	$	3,296.9	$	782.4	$	143.4	$	34,949.5
Securities loaned	2,273.5		—		—		—		2,273.5
Gross amount of secured financing	$	33,000.3	$	3,296.9	$	782.4	$	143.4	$	37,223.0


	September 30, 2025
	Overnight and Open		Less than 30 Days		30-90 Days		Over 90 Days		Total
Securities sold under agreements to repurchase	$	26,173.4	$	3,128.5	$	180.4	$	41.4	$	29,523.7
Securities loaned	2,550.8		—		—		—		2,550.8
Gross amount of secured financing	$	28,724.2	$	3,128.5	$	180.4	$	41.4	$	32,074.5

Schedule of Financial Instruments Owned and Pledged as Collateral

The following table sets forth the carrying value of repurchase agreements and securities lending agreements by class of collateral pledged (in millions):


Securities sold under agreements to repurchase	March 31, 2026		September 30, 2025
U.S. Treasury obligations	$	19,525.0	$	19,311.9
U.S. government agency obligations and municipal bonds	1,680.9		804.3
Asset-backed obligations	423.7		55.0
Agency mortgage-backed obligations	10,208.6		7,521.4
Foreign government obligations	1,400.9		881.4
Corporate bonds	1,710.4		949.7
Total securities sold under agreement to repurchase	$	34,949.5	$	29,523.7

Securities loaned
Equity securities	$	2,273.5	$	2,550.8
Total securities loaned	2,273.5		2,550.8
Gross amount of secured financing	$	37,223.0	$	32,074.5

The following tables provide the netting of securities purchased under agreements to resell, securities sold under agreements to repurchase, securities borrowed and securities loaned as of the periods indicated (in millions):


	March 31, 2026
Offsetting of collateralized transactions:	Gross Amounts Recognized		Amounts Offset in the Condensed Consolidated Balance Sheet		Net Amounts Presented in the Condensed Consolidated Balance Sheet
Securities purchased under agreements to resell	$	32,776.1	$	(17,575.0)	$	15,201.1
Securities borrowed	$	2,289.9	$	—	$	2,289.9
Securities sold under agreements to repurchase	$	34,949.5	$	(17,575.0)	$	17,374.5
Securities loaned	$	2,273.5	$	—	$	2,273.5


	September 30, 2025
Offsetting of collateralized transactions:	Gross Amounts Recognized		Amounts Offset in the Condensed Consolidated Balance Sheet		Net Amounts Presented in the Condensed Consolidated Balance Sheet
Securities purchased under agreements to resell	$	26,298.1	$	(15,972.7)	$	10,325.4
Securities borrowed	$	2,743.1	$	—	$	2,743.1
Securities sold under agreements to repurchase	$	29,523.7	$	(15,972.7)	$	13,551.0
Securities loaned	$	2,550.8	$	—	$	2,550.8

Schedule of Fair Values of Collateral Pledged, Received and Repledged

The following table sets forth the fair values, which approximate carrying value because of the short-term nature of collateral pledged, received and repledged (in millions):


	March 31, 2026		September 30, 2025
Securities pledged or repledged to cover collateral requirements for tri-party arrangements	$	11,975.1	$	9,757.7
Securities pledged as collateral that are subject to segregation rules	$	249.0	$	—
Securities received as collateral that may be repledged	$	35,948.4	$	32,452.0
Securities received as collateral that are subject to segregation rules	$	3,774.8	$	1,739.3
Securities received as collateral that may be repledged covering securities sold short	$	3,114.4	$	1,965.1
Repledged securities borrowed and client securities held under custodial clearing arrangements to collateralize securities loaned agreements	$	2,322.8	$	2,491.4

Credit Facilities (Tables)

6 Months Ended

Mar. 31, 2026

Debt Disclosure [Abstract]

Schedule of Debt

The following table sets forth a listing of credit facilities, the current committed amounts as of the report date on the facilities, and outstanding (in millions, except for percentages):


(in millions)							Amounts Outstanding
	Borrower	Security	Renewal/Expiration Date	Total Commitment			March 31, 2026			September 30, 2025
Committed Credit Facilities
	Senior StoneX Group Inc. Committed Credit Facility - Revolving Line of Credit	(1)	June 3, 2028	$	650.0		$	95.0	(5)	$	317.0
	R.J. O'Brien & Associates, LLC Subordinated Credit Facility	None	April 30, 2027	180.0			128.3		(5)	110.8
	StoneX Financial Inc.	None	October 27, 2026	325.0		(6)	—		(5)	—
	StoneX Commodity Solutions LLC	Certain assets	July 29, 2026	325.0			180.0		(5)	104.0
	Right Company LLC	Certain assets	October 1, 2026	15.0			9.0		(5)	—
	StoneX Financial Ltd.	None	October 6, 2026	175.0			—		(5)	90.0
	StoneX Financial Pte. Ltd.	None	September 4, 2026	15.0			—		(5)	—
				$	1,685.0		$	412.3		$	621.8






	Uncommitted Credit Facilities	Various	Various				152.5		(5)	153.9
	Note Payable to Bank	Certain equipment	December 1, 2025				—		(5)	6.3
	Senior Secured Notes due 2031	(2)	March 1, 2031			(3)	544.7		(3),(4)	544.1
	Senior Secured Notes due 2032	(2)	July 15, 2032				615.6		(3),(4)	614.9
Total outstanding borrowings							$	1,725.1		$	1,941.0

(1) The StoneX Group Inc. senior committed credit facility is a revolving facility secured by substantially all of the assets of StoneX Group Inc. and certain subsidiaries identified in the credit facility agreement as obligors, and pledged equity of certain subsidiaries identified in the credit facility as limited guarantors.

(2) The Notes and the related guarantees are secured by liens on substantially all of the Company’s and the guarantors’ assets, subject to certain customary and other exceptions and permitted liens. The liens on the assets that secure the Notes and the related guarantees are contractually subordinated to the liens on the assets that secure the Company’s and the guarantors’ existing and future first lien secured indebtedness, including indebtedness under the Company’s senior committed credit facility.

(3) Amounts outstanding under the Notes due 2031 are reported net of unamortized deferred financing costs of $5.3 million and $5.9 million, in the respective periods presented. Amounts outstanding under the Notes due 2032 are reported net of unamortized deferred financing costs of $9.4 million and $10.1 million, in the respective periods presented.

(4) Included in Senior secured borrowings, net on the Condensed Consolidated Balance Sheets.

(5) Included in Payables to Lenders under loans on the Condensed Consolidated Balance Sheets.

(6) R.J. O’Brien & Associates, LLC may borrow up to $50.0 million as part of the total commitment.

Acquisitions - R.J. O’Brien - Schedule of Aggregate Merger Consideration (Details) - USD ($) $ in Millions		3 Months Ended
	Apr. 14, 2025	Mar. 31, 2026	Sep. 30, 2025
Business Combination [Line Items]
Goodwill		$ 301.8	$ 298.3
R.J. O’Brien
Business Combination [Line Items]
Cash consideration	$ 651.9
Amounts receivable from sellers	(10.0)
Total merger consideration	942.0
Total fair value of intangible assets acquired	410.6
Goodwill	166.6
Goodwill adjustments		$ 7.8
R.J. O’Brien \| Common Stock
Business Combination [Line Items]
Merger consideration	$ 300.1

Earnings per Share

6 Months Ended

Mar. 31, 2026

Earnings Per Share [Abstract]

Earnings per Share

The Company presents basic and diluted earnings per share (“EPS”) using the two-class method, which requires all outstanding unvested share-based payment awards that contain rights to non-forfeitable dividends and therefore participate in undistributed earnings with common stockholders be included in computing earnings per share. Under the two-class method, net income is reduced by the amount of dividends declared in the period for each class of common stock and participating security. The remaining undistributed earnings are then allocated to common stock and participating securities, based on their respective rights to receive dividends. Restricted stock awards granted to certain employees and directors contain non-forfeitable rights to dividends at the same rate as common stock and are considered participating securities. Basic EPS has been computed by dividing net income by the weighted-average number of common shares outstanding.

The following is a reconciliation of the numerator and denominator of the diluted earnings per share computations for the periods presented below.


	Three Months Ended March 31,				Six Months Ended March 31,
(in millions, except share amounts)	2026		2025		2026		2025
Numerator:
Net income	$	174.3	$	71.7	$	313.3	$	156.8
Less: Allocation to participating securities	(5.4)		(2.1)		(10.0)		(4.8)
Net income allocated to common stockholders	$	168.9	$	69.6	$	303.3	$	152.0






Denominator:
Weighted average number of:
Common shares outstanding	76,498,598		70,184,147		76,174,376		69,903,861
Dilutive potential common shares outstanding:
Share-based awards	4,957,933		3,880,488		4,782,486		3,568,307
Diluted weighted-average common shares	81,456,531		74,064,635		80,956,862		73,472,168

The dilutive effect of share-based awards is reflected in diluted net income per share by applying the treasury stock method, which includes consideration of unamortized share-based compensation expense.

Options to purchase 394,013 and 389,271 shares of common stock for the three months ended March 31, 2026 and 2025, respectively, were excluded from the calculation of diluted earnings per share as they would have been anti-dilutive. Options to purchase 969,150 and 504,456 shares of common stock for the six months ended March 31, 2026 and 2025, respectively, were excluded from the calculation of diluted earnings per share as they would have been anti-dilutive.

Allowance for Doubtful Accounts (Tables)

6 Months Ended

Mar. 31, 2026

Receivables [Abstract]

Schedule of Financing Receivable, Allowance for Doubtful Accounts

Activity in the allowance for doubtful accounts for the six months ended March 31, 2026 was as follows:


(in millions)
Balance as of September 30, 2025	$	53.9
Provision for bad debts(1)	13.7
Allowance charge-offs	(3.5)

Other	(0.2)
Balance as of March 31, 2026	$	63.9
(1) $(0.1) million is included in bad debt expense for the six months ended March 31, 2026 on the Condensed Consolidated Income Statements, which is not included in the allowance.

Regulatory Capital Requirements (Tables)

6 Months Ended

Mar. 31, 2026

Capital and Other Regulatory Requirements [Abstract]

Schedule of Subsidiaries with Minimum Regulatory Requirements

The following table details those subsidiaries with minimum regulatory requirements in excess of $10.0 million along with the actual balance maintained as of that date.


(in millions)		As of March 31, 2026
Subsidiary	Regulatory Authority	Actual		Minimum Requirement
StoneX Financial Inc.	SEC and CFTC	$	536.4	$	359.2
StoneX Financial Ltd.	FCA	$	603.6	$	437.1
Gain Capital Group, LLC	CFTC and NFA	$	80.9	$	30.0
StoneX Financial Pte. Ltd.	MAS	$	144.8	$	40.1
StoneX Markets LLC	CFTC and NFA	$	261.5	$	166.4
R.J. O'Brien & Associates, LLC	CFTC and NFA	$	450.9	$	341.2

Earnings per Share - Narrative (Details) - shares	3 Months Ended		6 Months Ended
Earnings per Share - Narrative (Details) - shares	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Earnings Per Share [Abstract]
Antidilutive securities (in shares)	394,013	389,271	969,150	504,456

Earnings per Share (Tables)

6 Months Ended

Mar. 31, 2026

Earnings Per Share [Abstract]

Schedule of Calculation of Numerator and Denominator in Earnings per Share

The following is a reconciliation of the numerator and denominator of the diluted earnings per share computations for the periods presented below.


	Three Months Ended March 31,				Six Months Ended March 31,
(in millions, except share amounts)	2026		2025		2026		2025
Numerator:
Net income	$	174.3	$	71.7	$	313.3	$	156.8
Less: Allocation to participating securities	(5.4)		(2.1)		(10.0)		(4.8)
Net income allocated to common stockholders	$	168.9	$	69.6	$	303.3	$	152.0






Denominator:
Weighted average number of:
Common shares outstanding	76,498,598		70,184,147		76,174,376		69,903,861
Dilutive potential common shares outstanding:
Share-based awards	4,957,933		3,880,488		4,782,486		3,568,307
Diluted weighted-average common shares	81,456,531		74,064,635		80,956,862		73,472,168

Intangible Assets - Schedule of Expected Amortization Expense (Details) - USD ($) $ in Millions	Mar. 31, 2026	Sep. 30, 2025
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]
Fiscal 2026 (remaining months)	$ 16.7
Fiscal 2027	31.1
Fiscal 2028	30.0
Fiscal 2029	29.2
Fiscal 2030 and thereafter	329.1
Total intangible assets subject to amortization	$ 436.1	$ 431.9

Securities and Commodity Financing Transactions - Schedule of Underlying Collateral Types of Gross Obligations (Details) - USD ($) $ in Millions	Mar. 31, 2026	Sep. 30, 2025
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under agreements to repurchase	$ 34,949.5	$ 29,523.7
Securities loaned	2,273.5	2,550.8
Gross amount of secured financing	37,223.0	32,074.5
U.S. Treasury obligations
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under agreements to repurchase	19,525.0	19,311.9
U.S. government agency obligations and municipal bonds
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under agreements to repurchase	1,680.9	804.3
Asset-backed obligations
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under agreements to repurchase	423.7	55.0
Agency mortgage-backed obligations
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under agreements to repurchase	10,208.6	7,521.4
Foreign government obligations
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under agreements to repurchase	1,400.9	881.4
Corporate bonds
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under agreements to repurchase	1,710.4	949.7
Equity securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities loaned	$ 2,273.5	$ 2,550.8

Regulatory Capital Requirements

6 Months Ended

Mar. 31, 2026

Capital and Other Regulatory Requirements [Abstract]

Regulatory Capital Requirements

The Company’s activities are subject to significant governmental regulation, both in the U.S. and in the international jurisdictions in which it operates. Subsidiaries of the Company were in compliance with all of their regulatory requirements as of March 31, 2026. The following table details those subsidiaries with minimum regulatory requirements in excess of $10.0 million along with the actual balance maintained as of that date.


(in millions)		As of March 31, 2026
Subsidiary	Regulatory Authority	Actual		Minimum Requirement
StoneX Financial Inc.	SEC and CFTC	$	536.4	$	359.2
StoneX Financial Ltd.	FCA	$	603.6	$	437.1
Gain Capital Group, LLC	CFTC and NFA	$	80.9	$	30.0
StoneX Financial Pte. Ltd.	MAS	$	144.8	$	40.1
StoneX Markets LLC	CFTC and NFA	$	261.5	$	166.4
R.J. O'Brien & Associates, LLC	CFTC and NFA	$	450.9	$	341.2

Certain other subsidiaries of the Company, typically with a minimum requirement less than $10.0 million, are also subject to net capital requirements promulgated by authorities in the countries in which they operate. As of March 31, 2026, all of the Company’s subsidiaries were in compliance with their local regulatory requirements.

- Definition

The entire disclosure for regulatory capital requirement for depository and lending institutions. Institutions include, but not are not limited to, finance company, insured depository institution, bank holding company, savings and loan association holding company, bank and savings institution not federally insured, mortgage company, foreign financial institution and credit union.

+ References + Details

Revenue from Contracts with Clients (Tables)

6 Months Ended

Mar. 31, 2026

Revenue from Contract with Customer [Abstract]

Schedule of Disaggregation of Revenue


	Three Months Ended March 31,				Six Months Ended March 31,
(in millions)	2026		2025		2026		2025
Revenues from contracts with clients as a percentage of total revenues	3.0	%	2.2	%	3.0	%	2.3	%

The following table represents a disaggregation of the Company’s total revenues separated between revenues from contracts with clients and other sources of revenue for the periods indicated.


	Three Months Ended March 31,				Six Months Ended March 31,
(in millions)	2026		2025		2026		2025
Revenues from contracts with clients:
Commission and clearing fees:
Sales-based:
Exchange-traded futures and options	$	188.9	$	71.0	$	361.1	$	134.2
OTC derivative brokerage	1.6		2.5		4.8		5.3
Equities and fixed income	40.0		15.0		74.3		30.1
Mutual funds	1.0		0.8		1.8		1.6
Insurance and annuity products	4.1		3.3		7.5		6.5
Other	0.8		0.4		0.9		0.8
Total sales-based commission	236.4		93.0		450.4		178.5
Trailing:
Mutual funds	3.6		3.5		7.2		6.9
Insurance and annuity products	4.3		4.0		8.3		8.0
Total trailing commission	7.9		7.5		15.5		14.9

Clearing fees	97.8		48.0		176.8		92.1
Trade conversion fees	3.8		3.4		6.1		5.6
Other	1.6		12.4		3.7		22.5
Total commission and clearing fees	347.5		164.3		652.5		313.6
Consulting, management, and account fees:
Underwriting fees	8.6		0.2		20.5		0.5
Asset management fees	15.9		14.4		32.1		29.2
Advisory and consulting fees	10.0		9.2		22.9		17.8
Sweep program fees	9.6		11.4		20.2		23.0
Client account fees	18.2		6.5		39.7		12.7
Other	6.7		2.6		9.7		8.9
Total consulting, management, and account fees	69.0		44.3		145.1		92.1
Sales of physical commodities:
Precious metals sales under ASC Topic 606	966.2		611.8		1,785.6		1,077.8
Total revenues from contracts with clients	$	1,382.7	$	820.4	$	2,583.2	$	1,483.5

Method of revenue recognition:
Point-in-time	$	1,339.3	$	777.9	$	2,492.5	$	1,398.6
Time elapsed	43.4		42.5		90.7		84.9
Total revenues from contracts with clients	1,382.7		820.4		2,583.2		1,483.5
Other sources of revenues
Physical precious metals under ASC Topic 815	41,949.4		34,233.2		77,631.8		59,755.6
Physical agricultural and energy products	1,381.3		1,147.6		2,568.6		2,210.3
Principal gains, net	469.7		300.5		848.2		609.4
Interest income	577.8		389.0		1,159.0		767.2
Total revenues	$	45,760.9	$	36,890.7	$	84,790.8	$	64,826.0

Total revenues by primary geographic region:
United States	$	2,749.0	$	1,880.0	$	4,992.6	$	3,664.4
Europe	1,416.6		840.2		2,580.9		1,546.0
South America	183.4		141.7		379.1		305.0
Middle East and Asia	41,397.7		34,024.2		76,739.7		59,314.9
Other	14.2		4.6		98.5		(4.3)
Total revenues	$	45,760.9	$	36,890.7	$	84,790.8	$	64,826.0

Operating revenues by primary geographic region:
United States	$	1,087.4	$	728.6	$	2,095.8	$	1,364.0
Europe	297.6		102.7		537.7		308.9
South America	53.5		53.8		87.9		85.0
Middle East and Asia	114.2		59.6		222.9		120.9
Other	14.1		11.3		60.7		21.5
Total operating revenues	$	1,566.8	$	956.0	$	3,005.0	$	1,900.3

Schedule of Income and Expense

The following table indicates the relevant income and expense:


	Three Months Ended March 31,				Six Months Ended March 31,
(in millions)	2026		2025		2026		2025
Dividend income on long equity positions	$	34.8	$	37.3	$	70.9	$	72.9
Dividend expense on short equity positions	35.5		35.2		71.7		71.6
Dividend (expense)/income, net reported within Principal gains, net	$	(0.7)	$	2.1	$	(0.8)	$	1.3

Credit Facilities - Schedule of Debt (Details) - USD ($) $ in Millions	Mar. 31, 2026	Sep. 30, 2025
Line of Credit Facility [Line Items]
Lenders under loans	$ 564.8	$ 782.0
Uncommitted Credit Facilities	152.5	153.9
Note Payable to Bank	0.0	6.3
Total outstanding borrowings	1,725.1	1,941.0
Committed and Subordinated Credit Facilities
Line of Credit Facility [Line Items]
Total Commitment	1,685.0
Lenders under loans	412.3	621.8
Senior Secured Notes due 2031
Line of Credit Facility [Line Items]
Senior secured notes	544.7	544.1
Senior Secured Notes due 2032
Line of Credit Facility [Line Items]
Senior secured notes	615.6	614.9
Line of Credit \| Revolving Credit Facility \| Senior StoneX Group Inc. Committed Credit Facility - Revolving Line of Credit
Line of Credit Facility [Line Items]
Total Commitment	650.0
Lenders under loans	95.0	317.0
Line of Credit \| Revolving Credit Facility \| StoneX Financial Inc.
Line of Credit Facility [Line Items]
Total Commitment	325.0
Lenders under loans	0.0	0.0
Line of Credit \| Revolving Credit Facility \| StoneX Financial Inc. \| R.J. O'Brien & Associates, LLC
Line of Credit Facility [Line Items]
Total Commitment	50.0
Line of Credit \| Revolving Credit Facility \| StoneX Commodity Solutions LLC
Line of Credit Facility [Line Items]
Total Commitment	325.0
Lenders under loans	180.0	104.0
Line of Credit \| Revolving Credit Facility \| Right Company LLC
Line of Credit Facility [Line Items]
Total Commitment	15.0
Lenders under loans	9.0	0.0
Line of Credit \| Revolving Credit Facility \| StoneX Financial Ltd.
Line of Credit Facility [Line Items]
Total Commitment	175.0
Lenders under loans	0.0	90.0
Line of Credit \| Revolving Credit Facility \| StoneX Financial Pte. Ltd.
Line of Credit Facility [Line Items]
Total Commitment	15.0
Lenders under loans	0.0	0.0
Subordinated Debt \| Revolving Credit Facility \| R.J. O'Brien & Associates, LLC Subordinated Credit Facility
Line of Credit Facility [Line Items]
Total Commitment	180.0
Lenders under loans	128.3	110.8
Senior Notes \| Senior Secured Notes due 2031
Line of Credit Facility [Line Items]
Debt instrument, unamortized discount (premium) and debt issuance costs, net	5.3	5.9
Senior Notes \| Senior Secured Notes due 2032
Line of Credit Facility [Line Items]
Debt instrument, unamortized discount (premium) and debt issuance costs, net	$ 9.4	$ 10.1

Financial Instruments with Off-Balance Sheet Risk and Concentrations of Credit Risk - Schedule of Gross Derivative Assets and Liabilities (Details) contract in Millions, $ in Millions	Mar. 31, 2026 USD ($) contract	Sep. 30, 2025 USD ($) contract
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset	$ 11,190.7	$ 7,987.4
Derivative liability, fair value, gross liability	10,454.6	8,461.7
Impact of netting and collateral asset	(10,111.5)	(7,621.7)
Impact of netting and collateral liability	$ (10,049.3)	$ (7,594.3)
Derivative, number of instruments held \| contract	17.5	19.2
Total fair value included in Deposits with and receivables from broker-dealers, clearing organizations, and counterparties, net
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	$ 729.7	$ 107.7
Total fair value included in Receivable from clients, net
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	52.4	58.1
Total fair value included in Financial instruments owned, at fair value
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	297.1	199.9
Total fair value included in Payables to clients
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	(41.5)	530.7
Total fair value included in Payables to broker-dealers, clearing organizations and counterparties
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	5.8	38.4
Total fair value included in Financial instruments sold, not yet purchased, at fair value
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	441.0	298.3
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset	11,188.5	7,977.9
Derivative liability, fair value, gross liability	10,442.7	8,460.7
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset	2.2	9.5
Derivative liability, fair value, gross liability	11.9	1.0
Exchange-traded commodity derivatives \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset	5,944.9	2,487.3
Derivative liability, fair value, gross liability	5,889.0	2,528.6
OTC commodity derivatives \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset	2,851.2	3,580.7
Derivative liability, fair value, gross liability	2,427.4	3,517.4
Exchange-traded foreign exchange derivatives \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset	7.7	7.5
Derivative liability, fair value, gross liability	7.7	7.5
OTC foreign exchange derivatives \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset	557.5	749.5
Derivative liability, fair value, gross liability	418.6	1,264.0
Exchange-traded interest rate derivatives \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset	917.1	361.2
Derivative liability, fair value, gross liability	919.3	367.4
OTC interest rate derivatives \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset	79.2	148.3
Derivative liability, fair value, gross liability	85.5	148.3
OTC interest rate derivatives \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset	0.2	0.0
Derivative liability, fair value, gross liability	8.1	0.0
Exchange-traded equity index derivatives \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset	451.8	413.4
Derivative liability, fair value, gross liability	451.8	413.4
OTC equity and indices derivatives \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset	211.5	195.1
Derivative liability, fair value, gross liability	144.4	138.1
To be announced (“TBA”) and forward settling securities \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset	167.6	34.9
Derivative liability, fair value, gross liability	99.0	76.0
Foreign currency forward contracts \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset	2.0	9.5
Derivative liability, fair value, gross liability	$ 3.8	$ 1.0

Credit Facilities

6 Months Ended

Mar. 31, 2026

Debt Disclosure [Abstract]

Credit Facilities

Committed Credit Facilities

The Company and its subsidiaries have committed credit facilities under which they may borrow up to $1,685.0 million, subject to the terms and conditions of these facilities. The amounts outstanding under these credit facilities carry variable rates of interest, thus approximating fair value. The committed credit facilities generally have covenant requirements that relate to various leverage, debt to net worth, fixed charge, tangible net worth, excess net capital, or profitability measures. The Company and its subsidiaries were in compliance with all relevant covenants as of March 31, 2026.

Uncommitted Credit Facilities

The Company has access to certain uncommitted financing agreements that support its ordinary course securities and commodities inventories. The agreements are subject to certain borrowing terms and conditions.

Subordinated Credit Facility

The Company’s subsidiary, R.J. O’Brien & Associates, LLC, has a subordinated credit facility which allows it to borrow up to $180.0 million. As of March 31, 2026, the outstanding tranches of borrowings mature at various dates through March 17, 2027. The facility matures in April 2027, at which point no further draws can be made. The subordinated credit facility complies with the applicable regulatory requirements, and the borrowings are available for computing net capital under the CFTC’s net capital rule for R.J. O’Brien & Associates, LLC.

Note Payable to Bank

The Company had a note payable to a commercial bank related to the financing of certain equipment which secured the note. The note matured on December 1, 2025 and was fully paid off, with final payment of $6.3 million.

Senior Secured Notes

On March 1, 2024, the Company issued $550.0 million in aggregate principal amount of its 7.875% Notes due 2031 at the offering price of 100% of the aggregate principal amount. The Notes due 2031 are fully and unconditionally guaranteed, jointly and severally, on a senior secured second lien basis by each of the Company’s existing and future subsidiaries that guarantee indebtedness under the Company’s senior secured revolving credit facility and certain other senior indebtedness. Interest related to these notes is payable twice annually, in arrears. The Company incurred debt issuance costs of $7.7 million, which are being amortized over the term of the Notes due 2031 under the effective interest method.

On July 8, 2025, the Company issued $625.0 million in aggregate principal amount of its 6.875% Notes due 2032, in connection with the acquisition of R.J. O’Brien, at the offering price of 100% of the aggregate principal amount. The Notes due 2032 are fully and unconditionally guaranteed, jointly and severally, on a senior secured second lien basis by each of the Company’s existing and future subsidiaries that guarantee indebtedness under the Company’s senior secured revolving credit facility and certain other senior indebtedness. Interest related to these notes is payable twice annually, in arrears. The Company incurred debt issuance costs of $10.5 million, which are being amortized over the term of the Notes due 2032 under the effective interest method.

The following table sets forth a listing of credit facilities, the current committed amounts as of the report date on the facilities, and outstanding (in millions, except for percentages):


(in millions)							Amounts Outstanding
	Borrower	Security	Renewal/Expiration Date	Total Commitment			March 31, 2026			September 30, 2025
Committed Credit Facilities
	Senior StoneX Group Inc. Committed Credit Facility - Revolving Line of Credit	(1)	June 3, 2028	$	650.0		$	95.0	(5)	$	317.0
	R.J. O'Brien & Associates, LLC Subordinated Credit Facility	None	April 30, 2027	180.0			128.3		(5)	110.8
	StoneX Financial Inc.	None	October 27, 2026	325.0		(6)	—		(5)	—
	StoneX Commodity Solutions LLC	Certain assets	July 29, 2026	325.0			180.0		(5)	104.0
	Right Company LLC	Certain assets	October 1, 2026	15.0			9.0		(5)	—
	StoneX Financial Ltd.	None	October 6, 2026	175.0			—		(5)	90.0
	StoneX Financial Pte. Ltd.	None	September 4, 2026	15.0			—		(5)	—
				$	1,685.0		$	412.3		$	621.8






	Uncommitted Credit Facilities	Various	Various				152.5		(5)	153.9
	Note Payable to Bank	Certain equipment	December 1, 2025				—		(5)	6.3
	Senior Secured Notes due 2031	(2)	March 1, 2031			(3)	544.7		(3),(4)	544.1
	Senior Secured Notes due 2032	(2)	July 15, 2032				615.6		(3),(4)	614.9
Total outstanding borrowings							$	1,725.1		$	1,941.0

(4) Included in Senior secured borrowings, net on the Condensed Consolidated Balance Sheets.

(5) Included in Payables to Lenders under loans on the Condensed Consolidated Balance Sheets.

(6) R.J. O’Brien & Associates, LLC may borrow up to $50.0 million as part of the total commitment.

As reflected above, certain of the Company’s committed credit facilities are scheduled to expire during the next twelve months following the quarterly period ended March 31, 2026. The Company intends to renew or replace these facilities as they expire, and based on the Company’s liquidity position and capital structure, the Company believes it will be able to do so.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-8A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
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-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(2)
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-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
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-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 12: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 470
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/470/tableOfContent

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Name Accounting Standards Codification
-Section 50
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Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Name Accounting Standards Codification
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Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Name Accounting Standards Codification
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-Paragraph 1C
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Reference 20: http://www.xbrl.org/2003/role/disclosureRef
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Reference 21: http://www.xbrl.org/2003/role/disclosureRef
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Reference 22: http://www.xbrl.org/2003/role/disclosureRef
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Reference 23: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Basis of Presentation and Consolidation and Accounting Standards Adopted (Details)	Feb. 03, 2026 $ / shares	Mar. 31, 2026 $ / shares	Sep. 30, 2025 $ / shares
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Stock split, conversion ratio	1.5
Common stock - par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01

Goodwill - Schedule of Goodwill Reconciliation (Details) $ in Millions	6 Months Ended
	Mar. 31, 2026 USD ($)
Business Combination [Line Items]
Total Goodwill Recorded	$ 3.5
Intercam Advisors, Inc. and Intercam Securities, Inc. \| Self-Directed/Retail
Business Combination [Line Items]
Goodwill	0.4
Plantureux et Associés \| Commercial
Business Combination [Line Items]
Goodwill	2.9
WCS International Limited \| Payments
Business Combination [Line Items]
Goodwill	8.0
R.J. O’Brien & Associates, LLC \| Commercial
Business Combination [Line Items]
Goodwill adjustments	(3.4)
R.J. O’Brien & Associates, LLC \| Institutional
Business Combination [Line Items]
Goodwill adjustments	$ (4.4)

Financial Instruments with Off-Balance Sheet Risk and Concentrations of Credit Risk - Schedule of Accumulated Other Comprehensive Income Effects of Derivative Instruments (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Amount of Gain/(Loss) Recognized in Other Comprehensive Income on Derivatives, net of tax	$ (15.5)	$ 6.6	$ (18.2)	$ (0.3)
Interest rate contracts
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Amount of Gain/(Loss) Recognized in Other Comprehensive Income on Derivatives, net of tax	(10.2)	0.0	(10.3)	0.1
Foreign currency forward contracts
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Amount of Gain/(Loss) Recognized in Other Comprehensive Income on Derivatives, net of tax	$ (5.3)	$ 6.6	$ (7.9)	$ (0.4)

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

Physical Commodities Inventory (Details) - USD ($) $ in Millions	Mar. 31, 2026	Sep. 30, 2025
Inventory [Line Items]
Physical Agriculture and Energy	$ 303.8	$ 249.3
Precious metals - held by broker-dealer subsidiary	437.2	471.1
Physical commodities inventory, net	1,038.8	917.5
Physical Commodities Inventory - Precious Metals
Inventory [Line Items]
Precious metals - held by broker-dealer subsidiary	133.4	221.8
Precious metals - held by non-broker-dealer subsidiaries	601.6	$ 446.4
Raw materials	2.4
Work in process	$ 148.4

Financial Instruments with Off-Balance Sheet Risk and Concentrations of Credit Risk - Schedule of Notional Values For Derivatives Instrument (Details) - Designated as Hedging Instrument £ in Millions, zł in Millions, $ in Millions	Mar. 31, 2026 USD ($)	Mar. 31, 2026 PLN (zł)	Mar. 31, 2026 GBP (£)	Sep. 30, 2025 USD ($)	Sep. 30, 2025 PLN (zł)	Sep. 30, 2025 GBP (£)
Interest rate contracts
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Derivative, notional amount	$ 1,800.0			$ 0.0
Foreign currency forward contracts \| Polish Zloty
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Derivative, notional amount	54.8	zł 210.0		45.0	zł 180.0
Foreign currency forward contracts \| British Pound Sterling
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Derivative, notional amount	$ 167.0		£ 124.0	$ 120.4		£ 93.0

Intangible Assets

6 Months Ended

Mar. 31, 2026

Goodwill and Intangible Assets Disclosure [Abstract]

Intangible Assets

The gross and net carrying values of intangible assets as of the balance sheet dates, by major intangible asset class are as follows (in millions):


	March 31, 2026						September 30, 2025
	Gross Amount		Accumulated Amortization		Net Amount		Gross Amount		Accumulated Amortization		Net Amount
Intangible assets subject to amortization
Trade/domain names and other licenses	$	7.1	$	(3.4)	$	3.7	$	10.6	$	(4.9)	$	5.7
Software programs/platforms	2.4		(2.2)		0.2		2.4		(2.0)		0.4
Client and supplier base	465.9		(33.7)		432.2		445.0		(19.2)		425.8
Total intangible assets subject to amortization	475.4		(39.3)		436.1		458.0		(26.1)		431.9

Intangible assets not subject to amortization
Website domains	2.2		—		2.2		2.3		—		2.3
Business licenses	3.7		—		3.7		3.7		—		3.7
Total intangible assets not subject to amortization	5.9		—		5.9		6.0		—		6.0
Total intangible assets	$	481.3	$	(39.3)	$	442.0	$	464.0	$	(26.1)	$	437.9

Amortization expense related to intangible assets was $9.7 million and $1.2 million for the three months ended March 31, 2026 and 2025, respectively. Amortization expense related to intangible assets was $17.9 million and $2.3 million for the six months ended March 31, 2026 and 2025, respectively.

The Company wrote off $4.6 million of fully amortized intangible assets during the six months ended March 31, 2026.

As of March 31, 2026, estimated future amortization expense was as follows:


(in millions)
Fiscal 2026 (remaining months)	$	16.7
Fiscal 2027	31.1
Fiscal 2028	30.0
Fiscal 2029	29.2
Fiscal 2030 and thereafter	329.1
Total intangible assets subject to amortization	$	436.1

Cover - shares	6 Months Ended
Cover - shares	Mar. 31, 2026	May 04, 2026
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2026
Document Transition Report	false
Entity File Number	000-23554
Entity Registrant Name	StoneX Group Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	59-2921318
Entity Address, Address Line One	230 Park Ave
Entity Address, Address Line Two	10th Floor
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10169
City Area Code	(212)
Local Phone Number	485-3500
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	SNEX
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		79,251,496
Entity Central Index Key	0000913760
Current Fiscal Year End Date	--09-30
Document Fiscal Year Focus	2026
Document Fiscal Period Focus	Q2
Amendment Flag	false

Financial Instruments with Off-Balance Sheet Risk and Concentrations of Credit Risk - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2026	Mar. 31, 2026	Sep. 30, 2025
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments sold, not yet purchased	$ 3,789.2	$ 3,789.2	$ 2,919.8
Foreign Currency Forward Contracts
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Maximum length of time hedged in cash flow hedge		2 years
Commodities
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Derivatives, credit valuation allowances	6.4	$ 9.3
Derivatives
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments sold, not yet purchased	429.1	429.1	297.3
Fair Value, Recurring \| Derivatives \| Not Designated as Hedging Instrument
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments sold, not yet purchased	$ 429.1	$ 429.1	$ 297.3

- Definition

Fair value of obligations incurred from short sales.

+ References + Details

Commitments and Contingencies	6 Months Ended
Commitments and Contingencies	Mar. 31, 2026
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal Proceedings From time to time and in the ordinary course of business, the Company is involved in various legal actions and proceedings, including tort claims, contractual disputes, employment matters, and workers’ compensation claims. The Company carries insurance that provides protection against certain types of claims, up to the limits of the respective policy. Additionally, the Company is subject to extensive regulation and supervision by U.S. federal and international governmental agencies and various self-regulatory organizations. The Company and its advisors periodically engage with such regulatory agencies and organizations, in the context of examinations or otherwise, to respond to inquiries, informational requests, and investigations. From time to time, such engagements result in regulatory complaints or other matters, the resolution of which can include fines and other remediation. In November 2023, BTIG filed a civil complaint (the “BTIG complaint”) against the Company and StoneX Financial Inc. (“StoneX”) in San Francisco Superior Court (CGC-23-610525) seeking monetary damages and injunctive relief for, among other things, alleged theft of purported trade secrets by former BTIG employees later employed at StoneX. The proceedings moved to FINRA Arbitration and the court action was stayed. On August 7, 2024 and October 21, 2024, BTIG filed additional FINRA arbitration claims against certain employees of the Company. On March 12, 2026, StoneX received a final arbitration award from the FINRA arbitration panel adjudicating the claims against StoneX. The panel awarded StoneX $1.0 million in compensatory damages and awarded BTIG $2.9 million in damages. The panel found that these sums should be offset, resulting in a net payment to BTIG of $1.9 million, which was paid by the Company in March 2026. Finally, the panel denied BTIG’s request for injunctive relief and granted StoneX’s petition for declaratory relief, finding that StoneX did not tortiously interfere with the non-compete and non-solicitation provisions of BTIG’s employee agreements. All claims for additional relief, including punitive damages, treble damages and attorneys’ fees were denied. On May 4, 2026, StoneX and its employees fully and finally resolved all differences with BTIG and no additional claims remain. As part of this resolution, StoneX agreed to pay an immaterial amount to BTIG. The Company received from the U.S. Department of Justice (the “DOJ”) and the SEC subpoenas that the Company believes are related to conduct alleged in the BTIG complaint. The SEC concluded its investigation into the Company, indicating that it did not intend to recommend an enforcement action by the Commission against the Company. The Company continues to cooperate with the DOJ. The ultimate outcome of the DOJ subpoena cannot presently be determined. As of March 31, 2026 and September 30, 2025, the Condensed Consolidated Balance Sheets include loss contingency accruals which are not material, individually or in the aggregate, to the Company’s financial position or liquidity. Management does not currently believe exposure from loss contingencies in excess of the amounts accrued to be material to the Company’s earnings, financial position or liquidity.

Segment Analysis - Narrative (Details) market in Thousands	6 Months Ended
Segment Analysis - Narrative (Details) market in Thousands	Mar. 31, 2026 employee country market currency
Segment Reporting Information [Line Items]
Number of reportable segments not disclosed flag	segments
Number of employees \| employee	5,400
Number of countries in which entity operates (more than)	180
Self-Directed/Retail
Segment Reporting Information [Line Items]
Number of global financial markets (more than) \| market	18
Payments
Segment Reporting Information [Line Items]
Number of countries in which entity operates (more than)	180
Number of different types of foreign currencies (more than) \| currency	140

Financial Instruments with Off-Balance Sheet Risk and Concentrations of Credit Risk - Schedule of Fair Values of Derivative Instruments Designated for Hedging Held (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Mar. 31, 2026	Sep. 30, 2025
Derivatives, Fair Value [Line Items]
Asset Derivatives	$ 11,190.7	$ 7,987.4
Liability Derivatives	10,454.6	8,461.7
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Asset Derivatives	2.2	9.5
Derivative assets expected to be released from Other comprehensive income into current earnings:	1.8	8.0
Liability Derivatives	11.9	1.0
Derivative liabilities expected to be released from Other comprehensive income into current earnings:	7.4	0.0
Designated as Hedging Instrument \| Interest rate contracts
Derivatives, Fair Value [Line Items]
Asset Derivatives	0.2	0.0
Liability Derivatives	8.1	0.0
Derivative liabilities expected to be released from Other comprehensive income into current earnings:	4.1	0.0
Designated as Hedging Instrument \| Foreign currency forward contracts
Derivatives, Fair Value [Line Items]
Asset Derivatives	2.0	9.5
Derivative assets expected to be released from Other comprehensive income into current earnings:	1.8	8.0
Liability Derivatives	3.8	1.0
Derivative liabilities expected to be released from Other comprehensive income into current earnings:	$ 3.3	$ 0.0

- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References + Details

- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References + Details

Income Taxes	6 Months Ended
Income Taxes	Mar. 31, 2026
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The income tax provision for interim periods comprises income tax on ordinary income/(loss) at the most recent estimated annual effective income tax rate, adjusted for the income tax effect of discrete items. Management uses an estimated annual effective income tax rate based on the forecasted pretax income/(loss) and statutory tax rates in the various jurisdictions in which the Company operates. Current and Prior Period Tax Expense Income tax expense of $52.8 million and $25.4 million for the three months ended March 31, 2026 and 2025, respectively, reflects estimated federal, foreign, state and local income taxes. The Company’s effective tax rate was 23% and 26% for the three months ended March 31, 2026 and 2025, respectively. The effective tax rate was higher than the U.S. federal statutory rate of 21% for the three months ended March 31, 2026 due to U.S. state and local taxes, Global Intangible Low-Taxed Income (“GILTI”), GloBE minimum tax, U.S. and foreign permanent differences, and the amount of foreign earnings taxed at higher rates.

- Definition

The entire disclosure for income tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Paragraph 1
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Acquisitions (Tables)

6 Months Ended

Mar. 31, 2026

Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract]

Schedule of Aggregate Merger Consideration

The aggregate merger consideration was (in millions):


Cash consideration	$	651.9
Common stock	300.1
Amounts receivable from sellers	(10.0)
Total merger consideration	$	942.0

Total fair value of intangible assets acquired	$	410.6
Goodwill(1)	$	166.6
(1) The current period contains a reduction of Goodwill of $7.8 million, related to changes to the estimated fair value of acquired assets and liabilities

Schedule of Operating Revenues, Net Income and Pro Forma Information

For the three and six months ended March 31, 2026, the Company’s results include total operating revenues and net income from RJO, as follows (in millions):


	Three Months Ended March 31, 2026		Six Months Ended March 31, 2026
Operating revenue	$	213.5	$	414.5
Net income	$	20.9	$	40.3


	Three Months Ended March 31, 2025		Six Months Ended March 31, 2025
Total revenues	$	37,114.2	$	65,258.6
Operating revenues	$	1,179.5	$	2,332.9
Net income	$	94.4	$	173.9
Basic earnings per share	$	1.23	$	2.27
Diluted earnings per share	$	1.17	$	2.16

- Definition

Tabular disclosure of business combination. Includes, but is not limited to, recognized asset and liability.

+ References + Details

Earnings per Share - Schedule of Reconciliation of Numerator and Denominator of Diluted Earnings Per Share (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Numerator:
Net income	$ 174.3	$ 71.7	$ 313.3	$ 156.8
Less: Allocation to participating securities	(5.4)	(2.1)	(10.0)	(4.8)
Net income allocated to common stockholders, basic	168.9	69.6	303.3	152.0
Net income allocated to common stockholders, diluted	$ 168.9	$ 69.6	$ 303.3	$ 152.0
Denominator:
Common shares outstanding (in shares)	76,498,598	70,184,147	76,174,376	69,903,861
Dilutive potential common shares outstanding:
Share-based awards (in shares)	4,957,933	3,880,488	4,782,486	3,568,307
Diluted weighted-average common shares (in shares)	81,456,531	74,064,635	80,956,862	73,472,168

Accumulated Other Comprehensive Loss, Net

6 Months Ended

Mar. 31, 2026

Equity [Abstract]

Accumulated Other Comprehensive Loss, Net

Accumulated other comprehensive loss, net consists of gains and losses affecting stockholders’ equity that, under U.S. GAAP, are excluded from net income. Other comprehensive income includes net actuarial losses from defined benefit pension plans, foreign currency translation adjustments, and cash flow hedge gains or losses. See Note 4 for additional information on cash flow hedges.

The following table summarizes the changes in accumulated other comprehensive loss, net for the six months ended March 31, 2026.


(in millions)	Foreign Currency Translation Adjustment		Pension Benefits Adjustment		Cash Flow Hedge		Accumulated Other Comprehensive Loss, net
Balances as of September 30, 2025	$	(21.4)	$	(1.3)	$	6.7	$	(16.0)
Other comprehensive loss, net of tax	0.1		—		(18.2)		(18.1)
Balances as of March 31, 2026	$	(21.3)	$	(1.3)	$	(11.5)	$	(34.1)

Financial Instruments with Off-Balance Sheet Risk and Concentrations of Credit Risk (Tables)

6 Months Ended

Mar. 31, 2026

Financial Instruments with Off-Balance Sheet Risk and Concentrations of Credit Risk [Abstract]

Schedule of Derivative Instruments

Listed below are the fair values of the Company’s derivative assets and liabilities as of March 31, 2026 and September 30, 2025. Assets represent net unrealized gains and liabilities represent net unrealized losses.


	March 31, 2026				September 30, 2025
(in millions)	Assets (1)		Liabilities (1)		Assets (1)		Liabilities (1)
Derivative contracts not accounted for as hedges:
Exchange-traded commodity derivatives	$	5,944.9	$	5,889.0	$	2,487.3	$	2,528.6
OTC commodity derivatives	2,851.2		2,427.4		3,580.7		3,517.4
Exchange-traded foreign exchange derivatives	7.7		7.7		7.5		7.5
OTC foreign exchange derivatives	557.5		418.6		749.5		1,264.0
Exchange-traded interest rate derivatives	917.1		919.3		361.2		367.4
OTC interest rate derivatives	79.2		85.5		148.3		148.3
Exchange-traded equity index derivatives	451.8		451.8		413.4		413.4
OTC equity and indices derivatives	211.5		144.4		195.1		138.1
To be announced (“TBA”) and forward settling securities	167.6		99.0		34.9		76.0
Subtotal	11,188.5		10,442.7		7,977.9		8,460.7
Derivative contracts designated as hedging instruments:
Interest rate contracts	0.2		8.1		—		—
Foreign currency forward contracts	2.0		3.8		9.5		1.0
Subtotal	2.2		11.9		9.5		1.0
Gross fair value of derivative contracts	$	11,190.7	$	10,454.6	$	7,987.4	$	8,461.7
Impact of netting and collateral	(10,111.5)		(10,049.3)		(7,621.7)		(7,594.3)
Total fair value included in Deposits with and receivables from broker-dealers, clearing organizations, and counterparties, net	$	729.7			$	107.7
Total fair value included in Receivable from clients, net	$	52.4			$	58.1
Total fair value included in Financial instruments owned, at fair value	$	297.1			$	199.9
Total fair value included in Payables to clients			$	(41.5)			$	530.7
Total fair value included in Payables to broker-dealers, clearing organizations and counterparties			$	5.8			$	38.4
Total fair value included in Financial instruments sold, not yet purchased, at fair value			$	441.0			$	298.3

(1)As of March 31, 2026 and September 30, 2025, the Company’s derivative contract volume for open positions was approximately 17.5 million and 19.2 million contracts, respectively.

Schedule of Fair Value of Derivative Instruments Designated for Hedging

The fair values of derivative instruments designated for hedging held as of March 31, 2026 and September 30, 2025 are as follows:


		March 31, 2026		September 30, 2025
(in millions)	Balance Sheet Location	Fair Value		Fair Value
Asset Derivatives
Derivatives designated as hedging instruments:
Interest rate contracts	Financial instruments owned, net	$	0.2	$	—
Foreign currency forward contracts	Financial instruments owned, net	2.0		9.5
Total derivatives designated as hedging instruments		$	2.2	$	9.5

Derivative assets expected to be released from Other comprehensive income into current earnings:

Foreign currency forward contracts		$	1.8	$	8.0
Total expected to be released from Other comprehensive income into earnings		$	1.8	$	8.0

Liability Derivatives
Derivatives designated as hedging instruments:
Interest rate contracts	Financial instruments sold, not yet purchased	$	8.1	$	—
Foreign currency forward contracts	Financial instruments sold, not yet purchased	3.8		1.0
Total derivatives designated as hedging instruments		$	11.9	$	1.0

Derivative liabilities expected to be released from Other comprehensive income into current earnings:
Interest rate contracts		$	4.1	$	—
Foreign currency forward contracts		3.3		—
Total expected to be released from Other comprehensive income into earnings		$	7.4	$	—

Schedule of Notional Amounts of Outstanding Derivative Positions

The notional values of derivative instruments designated for hedging held as of March 31, 2026 and September 30, 2025 are as follows:


	March 31, 2026		September 30, 2025
(in millions)	Notional Value		Notional Value
Derivatives designated as hedging instruments:
Interest rate contracts	$	1,800.0	$	—
Foreign currency forward contracts:
Foreign currency forward contracts to purchase Polish Zloty:
Local currency	zł	210.0	zł	180.0
USD	$	54.8	$	45.0
Foreign currency forward contracts to purchase British Pound Sterling:
Local currency	£	124.0	£	93.0
USD	$	167.0	$	120.4

Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance

The Condensed Consolidated Income Statement effects of derivative instruments designated for hedging held for the three and six months ended March 31, 2026 and 2025 are as follows:


(in millions)	Income Statement Location	Three Months Ended March 31, 2026		Three Months Ended March 31, 2025
Total gain/(loss) reclassified from Accumulated Other Comprehensive Income into Income:
Interest rate contracts	Interest income	$	(1.2)	$	—
Foreign currency forward contracts	Compensation and benefits	1.7		2.2
Total derivatives designated as hedging instruments		$	0.5	$	2.2



Amount of gain reclassified from accumulated other comprehensive income into income as a result of a forecasted transaction that is no longer probable of occurring		$	—	$	—


(in millions)	Income Statement Location	Six Months Ended March 31, 2026		Six Months Ended March 31, 2025
Total gain/(loss) reclassified from Accumulated Other Comprehensive Income into Income:
Interest rate contracts	Interest Income	$	(2.2)	$	—
Foreign currency forward contracts	Compensation and benefits	6.8		3.0
Total derivatives designated as hedging instruments		$	4.6	$	3.0



Amount of gain reclassified from accumulated other comprehensive income into income as a result of a forecasted transaction that is no longer probable of occurring		$	—	$	—

The following table sets forth the Company’s net gains/(losses) related to derivative financial instruments for the three and six months ended March 31, 2026 and 2025 in accordance with the Derivatives and Hedging Topic of the ASC. The net gains/(losses) set forth below are included in Principal gains, net and Cost of sales of physical commodities in the Condensed Consolidated Income Statements.


	Three Months Ended March 31,				Six Months Ended March 31,
(in millions)	2026		2025		2026		2025
Commodities	$	103.5	$	131.2	$	211.8	$	186.0
Foreign exchange	22.0		21.7		36.7		67.1

Interest rate, equities, and indices	31.1		7.6		51.4		49.9
To be announced and forward settling securities	32.0		(73.2)		4.2		18.8
Net gains from derivative contracts	$	188.6	$	87.3	$	304.1	$	321.8

Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income

The accumulated other comprehensive income effects of derivative instruments designated for hedging held for the three and six months ended March 31, 2026 and 2025 are as follows:


	Amount of Gain/(Loss) Recognized in Other Comprehensive Income on Derivatives, net of tax
(in millions)	Three Months Ended March 31, 2026		Three Months Ended March 31, 2025
Derivatives in Cash Flow Hedging Relationships:
Interest rate contracts	$	(10.2)	$	—
Foreign currency forward contracts	(5.3)		6.6
Total	$	(15.5)	$	6.6


	Amount of Gain/(Loss) Recognized in Other Comprehensive Income on Derivatives, net of tax
(in millions)	Six Months Ended March 31, 2026		Six Months Ended March 31, 2025
Derivatives in Cash Flow Hedging Relationships:
Interest rate contracts	$	(10.3)	$	0.1
Foreign currency forward contracts	(7.9)		(0.4)
Total	$	(18.2)	$	(0.3)

Financial Instruments with Off-Balance Sheet Risk and Concentrations of Credit Risk

6 Months Ended

Mar. 31, 2026

Financial Instruments with Off-Balance Sheet Risk and Concentrations of Credit Risk [Abstract]

Financial Instruments with Off-Balance Sheet Risk and Concentrations of Credit Risk

The Company is party to certain financial instruments with off-balance sheet risk in the normal course of its business. The Company has sold financial instruments that it does not currently own and will therefore be obliged to purchase such financial instruments at a future date. The Company has recorded these obligations in the condensed consolidated financial statements as of March 31, 2026 and September 30, 2025 at the fair values of the related financial instruments. The Company will incur losses if the fair value of the underlying financial instruments increases subsequent to March 31, 2026. The total Financial instruments sold, not yet purchased of $3,789.2 million and $2,919.8 million as of March 31, 2026 and September 30, 2025, respectively, includes $429.1 million and $297.3 million for derivative contracts not designated as hedges, respectively, which represented a liability to the Company based on their fair values as of March 31, 2026 and September 30, 2025.

Derivatives

The Company utilizes derivative products in its trading capacity as a dealer in order to satisfy client needs and mitigate risk. The Company manages risks from both derivatives and non-derivative cash instruments on a consolidated basis. The risks of derivatives should not be viewed in isolation, but in aggregate with the Company’s other trading activities. The Company’s derivative positions are included in the Condensed Consolidated Balance Sheets in Deposits with and receivables from broker-dealers, clearing organizations and counterparties, Receivables from clients, net, Financial instruments owned and sold, not yet purchased, at fair value, Payable to clients, and Payables to broker-dealers, clearing organizations and counterparties.


	March 31, 2026				September 30, 2025
(in millions)	Assets (1)		Liabilities (1)		Assets (1)		Liabilities (1)
Derivative contracts not accounted for as hedges:
Exchange-traded commodity derivatives	$	5,944.9	$	5,889.0	$	2,487.3	$	2,528.6
OTC commodity derivatives	2,851.2		2,427.4		3,580.7		3,517.4
Exchange-traded foreign exchange derivatives	7.7		7.7		7.5		7.5
OTC foreign exchange derivatives	557.5		418.6		749.5		1,264.0
Exchange-traded interest rate derivatives	917.1		919.3		361.2		367.4
OTC interest rate derivatives	79.2		85.5		148.3		148.3
Exchange-traded equity index derivatives	451.8		451.8		413.4		413.4
OTC equity and indices derivatives	211.5		144.4		195.1		138.1
To be announced (“TBA”) and forward settling securities	167.6		99.0		34.9		76.0
Subtotal	11,188.5		10,442.7		7,977.9		8,460.7
Derivative contracts designated as hedging instruments:
Interest rate contracts	0.2		8.1		—		—
Foreign currency forward contracts	2.0		3.8		9.5		1.0
Subtotal	2.2		11.9		9.5		1.0
Gross fair value of derivative contracts	$	11,190.7	$	10,454.6	$	7,987.4	$	8,461.7
Impact of netting and collateral	(10,111.5)		(10,049.3)		(7,621.7)		(7,594.3)
Total fair value included in Deposits with and receivables from broker-dealers, clearing organizations, and counterparties, net	$	729.7			$	107.7
Total fair value included in Receivable from clients, net	$	52.4			$	58.1
Total fair value included in Financial instruments owned, at fair value	$	297.1			$	199.9
Total fair value included in Payables to clients			$	(41.5)			$	530.7
Total fair value included in Payables to broker-dealers, clearing organizations and counterparties			$	5.8			$	38.4
Total fair value included in Financial instruments sold, not yet purchased, at fair value			$	441.0			$	298.3

(1)As of March 31, 2026 and September 30, 2025, the Company’s derivative contract volume for open positions was approximately 17.5 million and 19.2 million contracts, respectively.

The Company’s derivative contracts are principally held in its Institutional, Commercial, and Self-Directed/Retail segments. The Company provides its Institutional segment clients access to exchanges at which they can carry out their trading strategies. The Company assists its Commercial segment clients in protecting the value of their future production by entering into option or forward agreements with them on an OTC basis. The Company also provides its Commercial segment clients with exchange products, including combinations of buying and selling puts and calls. In its Self-Directed/Retail segment, the Company provides its retail clients with access to spot foreign exchange, precious metals trading, as well as contracts for difference (“CFD”) and spread bets, where permitted. The Company mitigates its risk by generally offsetting the client’s transaction simultaneously with one of the Company’s trading counterparties or will offset that transaction with a similar but not identical position on the exchange. The risk mitigation of these offsetting trades is not within the documented hedging designation requirements of the Derivatives and Hedging Topic of the ASC. These derivative contracts are traded along with cash transactions because of the integrated nature of the markets for these products. The Company manages the risks associated with derivatives on an aggregate basis along with the risks associated with its proprietary trading and market-making activities in cash instruments as part of its firm-wide risk management policies. In particular, the risks related to derivative positions may be partially offset by inventory, other derivatives, or cash collateral paid or received.

Hedging Activities

The Company uses foreign currency derivatives, in the form of forward contracts, to hedge risk related to the variability in exchange rates relative to certain of the Company’s non-USD expenditures. These hedges are designated cash flow hedges, through which the Company mitigates variability in exchange rates by exchanging foreign currency for USD at fixed exchange rates at a pre-determined future date, or several cash flows at several pre-determined future dates. While the forward contracts mitigate exchange rate variability risk, they do introduce credit risk, which is the possibility that the Company’s trading counterparty fails to meet its obligation. The Company minimizes this risk by entering into its forward contracts with highly-rated, multi-national institutions. These hedges will all mature within 2 years from the end of the current period.

The Company also uses interest rate derivatives, in the form of swaps, to hedge risk related to variability in overnight rates. These hedges are designated cash flow hedges, through which the Company mitigates uncertainty in its interest income by converting floating-rate interest income to fixed-rate interest income. While the swaps mitigate interest rate risk, they do introduce credit risk, which is the possibility that the Company’s trading counterparty fails to meet its obligation. The Company minimizes this risk by entering into its swaps with highly-rated, multi-national institutions. In addition to credit risk, there is limited market risk associated with the swap positions. The Company’s market risk is limited, because any amounts the Company must pay from having exchanged variable interest will be funded by the variable interest the Company receives on its deposits. These hedges will all mature within 2 years from the end of the current period.

The Company assesses the effectiveness of its hedges at each reporting period to identify any required reclassifications into current earnings. During the three and six months ended March 31, 2026 and 2025, the Company did not designate any portion of its hedges as ineffective and thus did not have any values in current earnings related to ineffective hedges.

The fair values of derivative instruments designated for hedging held as of March 31, 2026 and September 30, 2025 are as follows:


		March 31, 2026		September 30, 2025
(in millions)	Balance Sheet Location	Fair Value		Fair Value
Asset Derivatives
Derivatives designated as hedging instruments:
Interest rate contracts	Financial instruments owned, net	$	0.2	$	—
Foreign currency forward contracts	Financial instruments owned, net	2.0		9.5
Total derivatives designated as hedging instruments		$	2.2	$	9.5

Derivative assets expected to be released from Other comprehensive income into current earnings:

Foreign currency forward contracts		$	1.8	$	8.0
Total expected to be released from Other comprehensive income into earnings		$	1.8	$	8.0

Liability Derivatives
Derivatives designated as hedging instruments:
Interest rate contracts	Financial instruments sold, not yet purchased	$	8.1	$	—
Foreign currency forward contracts	Financial instruments sold, not yet purchased	3.8		1.0
Total derivatives designated as hedging instruments		$	11.9	$	1.0

Derivative liabilities expected to be released from Other comprehensive income into current earnings:
Interest rate contracts		$	4.1	$	—
Foreign currency forward contracts		3.3		—
Total expected to be released from Other comprehensive income into earnings		$	7.4	$	—

The notional values of derivative instruments designated for hedging held as of March 31, 2026 and September 30, 2025 are as follows:


	March 31, 2026		September 30, 2025
(in millions)	Notional Value		Notional Value
Derivatives designated as hedging instruments:
Interest rate contracts	$	1,800.0	$	—
Foreign currency forward contracts:
Foreign currency forward contracts to purchase Polish Zloty:
Local currency	zł	210.0	zł	180.0
USD	$	54.8	$	45.0
Foreign currency forward contracts to purchase British Pound Sterling:
Local currency	£	124.0	£	93.0
USD	$	167.0	$	120.4

The Condensed Consolidated Income Statement effects of derivative instruments designated for hedging held for the three and six months ended March 31, 2026 and 2025 are as follows:


(in millions)	Income Statement Location	Three Months Ended March 31, 2026		Three Months Ended March 31, 2025
Total gain/(loss) reclassified from Accumulated Other Comprehensive Income into Income:
Interest rate contracts	Interest income	$	(1.2)	$	—
Foreign currency forward contracts	Compensation and benefits	1.7		2.2
Total derivatives designated as hedging instruments		$	0.5	$	2.2



Amount of gain reclassified from accumulated other comprehensive income into income as a result of a forecasted transaction that is no longer probable of occurring		$	—	$	—


(in millions)	Income Statement Location	Six Months Ended March 31, 2026		Six Months Ended March 31, 2025
Total gain/(loss) reclassified from Accumulated Other Comprehensive Income into Income:
Interest rate contracts	Interest Income	$	(2.2)	$	—
Foreign currency forward contracts	Compensation and benefits	6.8		3.0
Total derivatives designated as hedging instruments		$	4.6	$	3.0



Amount of gain reclassified from accumulated other comprehensive income into income as a result of a forecasted transaction that is no longer probable of occurring		$	—	$	—

The accumulated other comprehensive income effects of derivative instruments designated for hedging held for the three and six months ended March 31, 2026 and 2025 are as follows:


	Amount of Gain/(Loss) Recognized in Other Comprehensive Income on Derivatives, net of tax
(in millions)	Three Months Ended March 31, 2026		Three Months Ended March 31, 2025
Derivatives in Cash Flow Hedging Relationships:
Interest rate contracts	$	(10.2)	$	—
Foreign currency forward contracts	(5.3)		6.6
Total	$	(15.5)	$	6.6


	Amount of Gain/(Loss) Recognized in Other Comprehensive Income on Derivatives, net of tax
(in millions)	Six Months Ended March 31, 2026		Six Months Ended March 31, 2025
Derivatives in Cash Flow Hedging Relationships:
Interest rate contracts	$	(10.3)	$	0.1
Foreign currency forward contracts	(7.9)		(0.4)
Total	$	(18.2)	$	(0.3)


	Three Months Ended March 31,				Six Months Ended March 31,
(in millions)	2026		2025		2026		2025
Commodities	$	103.5	$	131.2	$	211.8	$	186.0
Foreign exchange	22.0		21.7		36.7		67.1

Interest rate, equities, and indices	31.1		7.6		51.4		49.9
To be announced and forward settling securities	32.0		(73.2)		4.2		18.8
Net gains from derivative contracts	$	188.6	$	87.3	$	304.1	$	321.8

During the three and six months ended March 31, 2026, Commodities is net of credit valuation allowances of $6.4 million and $9.3 million, respectively, related to the non-performance of a counterparty under derivative contracts in precious metals.

Credit Risk

In the normal course of business, the Company purchases and sells financial instruments, commodities and foreign currencies as either a principal or agent on behalf of its clients. If either the client or counterparty fails to perform, the Company may be required to discharge the obligations of the nonperforming party. In such circumstances, the Company may sustain a loss if the fair value of the financial instrument, commodity, or foreign currency is different from the contract value of the transaction.

The majority of the Company’s transactions and, consequently, the concentration of its credit exposure are with commodity exchanges, clients, broker-dealers and other financial institutions. These activities primarily involve collateralized and uncollateralized arrangements and may result in credit exposure in the event that a counterparty fails to meet its contractual obligations. The Company’s exposure to credit risk can be directly impacted by volatile financial markets, which may impair counterparties’ ability to satisfy contractual obligations. The Company seeks to control its credit risk through a variety of reporting and control procedures, including establishing credit and/or position limits based upon a review of the counterparties’ financial condition and credit ratings. The Company monitors collateral levels on a daily basis for compliance with regulatory and internal guidelines and requests changes in collateral levels as appropriate.

The Company is a party to financial instruments in the normal course of its business through client and proprietary trading accounts in exchange-traded and OTC derivative instruments. These instruments are primarily the result of the execution of orders for commodity futures, options on futures, OTC swaps and options and spot and forward foreign currency contracts on behalf of its clients, substantially all of which are transacted on a margin basis. Such transactions may expose the Company to significant credit risk in the event that margin requirements are not sufficient to fully cover losses which clients may incur. The Company controls the risks associated with these transactions by requiring clients to maintain margin deposits in compliance with individual exchange regulations and internal guidelines. The Company monitors required margin levels daily, and therefore, may require clients to deposit additional collateral or reduce positions when necessary. The Company also establishes credit limits for clients, which are monitored daily. The Company evaluates each client’s creditworthiness on a case-by-case basis. Clearing, financing, and settlement activities may require the Company to maintain funds with or pledge securities as collateral with other financial institutions. Generally, these exposures to both clients and exchanges are subject to master netting, or client agreements, which reduce the exposure to the Company by permitting receivables and payables with such clients to be offset in the event of a client default. Management believes that the margin deposits held as of March 31, 2026 and September 30, 2025 were adequate to minimize the risk of material loss that could be created by positions held at that time. Additionally, the Company monitors collateral fair value on a daily basis and adjusts collateral levels in the event of excess market exposure.

Derivative financial instruments involve varying degrees of off-balance sheet market risk whereby changes in the fair values of underlying financial instruments may result in changes in the fair value of the financial instruments in excess of the amounts reflected in the Condensed Consolidated Balance Sheets. Exposure to market risk is influenced by a number of factors, including the relationships between the financial instruments and the Company’s positions, as well as the volatility and liquidity in the markets in which the financial instruments are traded. The principal risk components of financial instruments include, among other things, interest rate volatility, the duration of the underlying instruments and changes in commodity pricing and foreign exchange rates. The Company attempts to manage its exposure to market risk through various techniques. Aggregate market limits have been established and market risk measures are routinely monitored against these limits.

- Definition

The entire disclosure for derivative instruments and hedging activities including, but not limited to, risk management strategies, non-hedging derivative instruments, assets, liabilities, revenue and expenses, and methodologies and assumptions used in determining the amounts.

+ References

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+ Details

Securities and Commodity Financing Transactions - Schedule of Collateral Maturities of Gross Obligations (Details) - USD ($) $ in Millions	Mar. 31, 2026	Sep. 30, 2025
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under agreements to repurchase	$ 34,949.5	$ 29,523.7
Securities loaned	2,273.5	2,550.8
Gross amount of secured financing	37,223.0	32,074.5
Overnight and Open
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under agreements to repurchase	30,726.8	26,173.4
Securities loaned	2,273.5	2,550.8
Gross amount of secured financing	33,000.3	28,724.2
Less than 30 Days
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under agreements to repurchase	3,296.9	3,128.5
Securities loaned	0.0	0.0
Gross amount of secured financing	3,296.9	3,128.5
30-90 Days
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under agreements to repurchase	782.4	180.4
Securities loaned	0.0	0.0
Gross amount of secured financing	782.4	180.4
Over 90 Days
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under agreements to repurchase	143.4	41.4
Securities loaned	0.0	0.0
Gross amount of secured financing	$ 143.4	$ 41.4

- Definition

Amount, after the effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References + Details

Segment Analysis - Schedule of Segment Reporting Information Examples (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025	Sep. 30, 2025
Segment Reporting Information [Line Items]
Non-interest revenues	$ 45,183.1	$ 36,501.7	$ 83,631.8	$ 64,058.8
Interest income	577.8	389.0	1,159.0	767.2
Total revenues	45,760.9	36,890.7	84,790.8	64,826.0
Cost of sales of physical commodities	44,194.1	35,934.7	81,785.8	62,925.7
Total operating revenues	1,566.8	956.0	3,005.0	1,900.3
Transaction-based clearing expenses	152.7	91.8	285.3	178.3
Introducing broker commissions	97.4	45.5	190.6	89.8
Total interest expense	487.6	331.4	975.6	652.8
Net operating revenues	829.1	487.3	1,553.5	979.4
Variable compensation and benefits	248.5	146.7	464.4	280.0
Net contribution	580.6	340.6	1,089.1	699.4
Fixed compensation and benefits	158.7	120.4	298.7	239.6
Trading systems and market information	25.8	19.5	50.8	39.5
Professional fees	18.4	16.5	51.2	35.5
Non-trading technology and support	28.4	20.9	55.0	40.6
Selling and marketing	14.0	13.4	28.1	25.4
Travel and business development	16.8	7.1	28.6	15.5
Depreciation and amortization	26.9	15.6	51.9	31.3
Bad debts, net of recoveries	12.4	0.1	13.6	1.9
Shared services	0.0	0.0	0.0	0.0
Other fixed expenses	49.4	30.0	96.1	61.8
Non-variable expenses	350.8	243.5	674.0	491.1
Other losses	(2.7)		(3.1)	5.7
Income before tax	227.1	97.1	412.0	214.0
Total assets	53,626.9		53,626.9		$ 45,268.0
Operating Segments \| Commercial
Segment Reporting Information [Line Items]
Non-interest revenues	44,646.1	36,138.4	82,585.2	63,310.9
Interest income	85.7	46.1	165.6	99.4
Total revenues	44,731.8	36,184.5	82,750.8	63,410.3
Cost of sales of physical commodities	44,194.2	35,934.7	81,785.8	62,925.7
Total operating revenues	537.6	249.8	965.0	484.6
Transaction-based clearing expenses	41.9	19.1	72.2	36.7
Introducing broker commissions	51.7	13.1	101.6	24.4
Total interest expense	33.8	23.3	64.7	37.7
Net operating revenues	410.2	194.3	726.5	385.8
Variable compensation and benefits	95.1	53.4	176.2	97.1
Net contribution	315.1	140.9	550.3	288.7
Fixed compensation and benefits	24.5	19.8	47.0	36.9
Trading systems and market information	5.5	4.7	10.2	8.7
Professional fees	1.6	1.9	4.0	4.0
Non-trading technology and support	0.6	0.4	1.1	0.8
Selling and marketing	1.8	1.2	2.6	2.5
Travel and business development	2.7	2.0	5.9	4.3
Depreciation and amortization	6.1	2.1	11.6	3.9
Bad debts, net of recoveries	10.4	(0.3)	11.4	0.9
Shared services	11.8	7.0	21.1	13.8
Other fixed expenses	5.8	4.9	12.0	11.6
Non-variable expenses	70.8	43.7	126.9	87.4
Other losses	0.0		0.0	0.0
Income before tax	244.3	97.2	423.4	201.3
Total assets	10,896.2		10,896.2		9,826.3
Operating Segments \| Institutional
Segment Reporting Information [Line Items]
Non-interest revenues	372.6	223.8	737.3	438.4
Interest income	495.8	337.4	997.1	662.4
Total revenues	868.4	561.2	1,734.4	1,100.8
Cost of sales of physical commodities	0.0	0.0	0.0	0.0
Total operating revenues	868.4	561.2	1,734.4	1,100.8
Transaction-based clearing expenses	102.3	67.1	197.6	130.1
Introducing broker commissions	17.0	7.2	31.7	15.3
Total interest expense	433.6	295.9	865.4	590.4
Net operating revenues	315.5	191.0	639.7	365.0
Variable compensation and benefits	114.2	62.5	221.5	118.7
Net contribution	201.3	128.5	418.2	246.3
Fixed compensation and benefits	36.7	21.8	63.1	40.4
Trading systems and market information	10.3	7.7	21.8	15.6
Professional fees	3.0	1.9	18.2	6.6
Non-trading technology and support	1.2	1.0	2.7	1.9
Selling and marketing	1.2	0.8	2.5	1.8
Travel and business development	2.8	1.9	6.1	4.3
Depreciation and amortization	5.5	1.0	10.9	2.0
Bad debts, net of recoveries	1.5	(0.1)	1.6	(0.1)
Shared services	7.0	3.5	13.7	6.9
Other fixed expenses	8.7	2.5	14.9	3.6
Non-variable expenses	77.9	42.0	155.5	83.0
Other losses	(2.5)		(2.5)	1.3
Income before tax	120.9	86.5	260.2	164.6
Total assets	38,787.2		38,787.2		32,465.5
Operating Segments \| Self-Directed/Retail
Segment Reporting Information [Line Items]
Non-interest revenues	98.7	84.6	185.6	197.9
Interest income	7.8	7.6	15.3	15.9
Total revenues	106.5	92.2	200.9	213.8
Cost of sales of physical commodities	0.0	0.0	0.0	0.0
Total operating revenues	106.5	92.2	200.9	213.8
Transaction-based clearing expenses	4.5	3.2	8.1	6.6
Introducing broker commissions	27.4	24.2	54.8	48.2
Total interest expense	2.2	1.8	4.3	3.7
Net operating revenues	72.4	63.0	133.7	155.3
Variable compensation and benefits	4.3	4.6	9.4	7.4
Net contribution	68.1	58.4	124.3	147.9
Fixed compensation and benefits	8.6	8.8	15.9	18.1
Trading systems and market information	3.2	3.3	6.1	6.8
Professional fees	1.5	2.8	3.4	5.4
Non-trading technology and support	2.1	2.6	3.7	4.7
Selling and marketing	8.6	8.9	16.9	17.6
Travel and business development	0.5	0.5	1.0	1.1
Depreciation and amortization	3.8	4.3	6.8	9.6
Bad debts, net of recoveries	0.5	0.6	0.6	1.1
Shared services	3.7	2.3	6.9	5.4
Other fixed expenses	5.4	2.8	14.5	6.0
Non-variable expenses	37.9	36.9	75.8	75.8
Other losses	0.0		0.0	4.4
Income before tax	30.2	21.5	48.5	76.5
Total assets	1,342.2		1,342.2		1,256.2
Operating Segments \| Payments
Segment Reporting Information [Line Items]
Non-interest revenues	55.7	49.8	112.4	107.3
Interest income	0.3	0.5	0.6	1.1
Total revenues	56.0	50.3	113.0	108.4
Cost of sales of physical commodities	0.0	0.0	0.0	0.0
Total operating revenues	56.0	50.3	113.0	108.4
Transaction-based clearing expenses	2.2	1.7	4.2	3.5
Introducing broker commissions	1.3	1.0	2.3	1.9
Total interest expense	0.0	0.0	0.0	0.0
Net operating revenues	52.5	47.6	106.5	103.0
Variable compensation and benefits	8.8	8.8	17.4	17.9
Net contribution	43.7	38.8	89.1	85.1
Fixed compensation and benefits	5.3	7.4	10.2	14.0
Trading systems and market information	0.2	0.3	0.4	0.7
Professional fees	1.0	1.2	1.4	1.9
Non-trading technology and support	0.4	0.5	0.7	1.0
Selling and marketing	0.1	0.2	0.2	0.3
Travel and business development	0.2	0.3	0.5	0.6
Depreciation and amortization	1.3	1.2	2.6	2.2
Bad debts, net of recoveries	0.0	(0.1)	0.0	0.0
Shared services	2.5	2.1	5.4	4.2
Other fixed expenses	0.7	1.2	1.4	1.6
Non-variable expenses	11.7	14.3	22.8	26.5
Other losses	(0.2)		(0.6)	0.0
Income before tax	31.8	24.5	65.7	58.6
Total assets	606.1		606.1		722.5
Corporate
Segment Reporting Information [Line Items]
Non-interest revenues	10.9	5.9	13.0	5.9
Interest income	8.8	10.8	18.9	21.9
Total revenues	19.7	16.7	31.9	27.8
Cost of sales of physical commodities	(0.1)	0.0	0.0	0.0
Total operating revenues	19.8	16.7	31.9	27.8
Transaction-based clearing expenses	2.7	1.5	4.9	3.0
Introducing broker commissions	0.0	0.0	0.2	0.0
Total interest expense	38.6	23.8	79.7	54.5
Net operating revenues	(21.5)	(8.6)	(52.9)	(29.7)
Variable compensation and benefits	26.1	17.4	39.9	38.9
Net contribution	(47.6)	(26.0)	(92.8)	(68.6)
Fixed compensation and benefits	83.6	62.6	162.5	130.2
Trading systems and market information	6.6	3.5	12.3	7.7
Professional fees	11.3	8.7	24.2	17.6
Non-trading technology and support	24.1	16.4	46.8	32.2
Selling and marketing	2.3	2.3	5.9	3.2
Travel and business development	10.6	2.4	15.1	5.2
Depreciation and amortization	10.2	7.0	20.0	13.6
Bad debts, net of recoveries	0.0	0.0	0.0	0.0
Shared services	(25.0)	(14.9)	(47.1)	(30.3)
Other fixed expenses	28.8	18.6	53.3	39.0
Non-variable expenses	152.5	106.6	293.0	218.4
Other losses	0.0		0.0	0.0
Income before tax	(200.1)	(132.6)	(385.8)	(287.0)
Total assets	1,995.2		1,995.2		997.5
Eliminations
Segment Reporting Information [Line Items]
Non-interest revenues	(0.9)	(0.8)	(1.7)	(1.6)
Interest income	(20.6)	(13.4)	(38.5)	(33.5)
Total revenues	(21.5)	(14.2)	(40.2)	(35.1)
Cost of sales of physical commodities	0.0	0.0	0.0	0.0
Total operating revenues	(21.5)	(14.2)	(40.2)	(35.1)
Transaction-based clearing expenses	(0.9)	(0.8)	(1.7)	(1.6)
Introducing broker commissions	0.0	0.0	0.0	0.0
Total interest expense	(20.6)	(13.4)	(38.5)	(33.5)
Net operating revenues	0.0	0.0	0.0	0.0
Variable compensation and benefits	0.0	0.0	0.0	0.0
Net contribution	0.0	0.0	0.0	0.0
Fixed compensation and benefits	0.0	0.0	0.0	0.0
Trading systems and market information	0.0	0.0	0.0	0.0
Professional fees	0.0	0.0	0.0	0.0
Non-trading technology and support	0.0	0.0	0.0	0.0
Selling and marketing	0.0	0.0	0.0	0.0
Travel and business development	0.0	0.0	0.0	0.0
Depreciation and amortization	0.0	0.0	0.0	0.0
Bad debts, net of recoveries	0.0	0.0	0.0	0.0
Shared services	0.0	0.0	0.0	0.0
Other fixed expenses	0.0	0.0	0.0	0.0
Non-variable expenses	0.0	0.0	0.0	0.0
Other losses	0.0		0.0	0.0
Income before tax	0.0	$ 0.0	0.0	$ 0.0
Total assets	$ 0.0		$ 0.0		$ 0.0

Financial Instruments with Off-Balance Sheet Risk and Concentrations of Credit Risk - Schedule of Income Statement Effects of Derivative Instruments (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Total derivatives designated as hedging instruments	$ 0.5	$ 2.2	$ 4.6	$ 3.0
Amount of gain reclassified from accumulated other comprehensive income into income as a result of a forecasted transaction that is no longer probable of occurring	0.0	0.0	0.0	0.0
Interest rate contracts
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Total derivatives designated as hedging instruments	31.1	7.6	51.4	49.9
Interest rate contracts \| Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Total derivatives designated as hedging instruments	(1.2)	0.0	(2.2)	0.0
Foreign currency forward contracts \| Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Total derivatives designated as hedging instruments	$ 1.7	$ 2.2	$ 6.8	$ 3.0

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

Securities and Commodity Financing Transactions - Schedule of Netting of Securities Purchased Under Agreements (Details) - USD ($) $ in Millions	Mar. 31, 2026	Sep. 30, 2025
Broker-Dealer [Abstract]
Securities purchased under agreements to resell, gross	$ 32,776.1	$ 26,298.1
Securities purchased under agreements to resell, offset	(17,575.0)	(15,972.7)
Securities purchased under agreements to resell, net	15,201.1	10,325.4
Securities borrowed, gross	2,289.9	2,743.1
Securities borrowed, net	2,289.9	2,743.1
Securities sold under agreements to repurchase, gross	34,949.5	29,523.7
Securities sold under agreements to repurchase, offset	(17,575.0)	(15,972.7)
Securities sold under agreements to repurchase, net	17,374.5	13,551.0
Securities loaned, gross	2,273.5	2,550.8
Securities loaned, net	$ 2,273.5	$ 2,550.8

Financial Instruments with Off-Balance Sheet Risk and Concentrations of Credit Risk - Schedule of Net Gains/(Losses) from Derivative Contracts (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Commodities
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) recognized in income, net	$ 103.5	$ 131.2	$ 211.8	$ 186.0
Foreign exchange
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) recognized in income, net	22.0	21.7	36.7	67.1
Interest rate, equities, and indices
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) recognized in income, net	31.1	7.6	51.4	49.9
To be announced and forward settling securities
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) recognized in income, net	32.0	(73.2)	4.2	18.8
Net gains from derivative contracts
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) recognized in income, net	$ 188.6	$ 87.3	$ 304.1	$ 321.8

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4C
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-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4C

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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Reference 19: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Allowance for Doubtful Accounts - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2026	Sep. 30, 2025
Receivables [Abstract]
Allowance for doubtful accounts receivable	$ 63.8	$ 53.9
Allowance for doubtful accounts - deposits with and receivables from broker-dealers, clearings organizations, and counterparties	$ 0.1	$ 0.0

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Mar. 31, 2026	Sep. 30, 2025
ASSETS
Cash and cash equivalents	$ 2,122.6	$ 1,605.8
Cash, securities and other assets segregated under federal and other regulations (including $1,117.4 million and $950.0 million at fair value at March 31, 2026 and September 30, 2025, respectively)	6,494.0	5,271.0
Collateralized transactions:
Securities purchased under agreements to resell	15,201.1	10,325.4
Securities borrowed	2,289.9	2,743.1
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net (including $5,307.6 million and $6,442.9 million at fair value at March 31, 2026 and September 30, 2025, respectively)	12,095.0	12,890.7
Receivable from clients, net (including $52.4 million and $58.1 million at fair value at March 31, 2026 and September 30, 2025, respectively)	1,401.1	1,333.9
Income taxes receivable	55.6	45.7
Financial instruments owned, at fair value (includes securities pledged as collateral that can be sold or repledged of $2,193.9 million and $1,165.8 million at March 31, 2026 and September 30, 2025, respectively)	11,261.9	8,604.4
Physical commodities inventory, net (including $437.2 million and $471.1 million at fair value at March 31, 2026 and September 30, 2025, respectively)	1,038.8	917.5
Deferred tax asset, net	30.3	32.0
Property and equipment, net	167.8	166.6
Operating right of use assets	169.3	161.9
Goodwill and intangible assets, net	743.8	736.2
Other assets	555.7	433.8
Total assets	53,626.9	45,268.0
Liabilities:
Accounts payable and other accrued liabilities (including $59.8 million and $32.3 million at fair value at March 31, 2026 and September 30, 2025, respectively)	867.4	769.1
Operating lease liabilities	219.3	211.7
Payables to:
Clients (including $(41.5) million and $530.7 million at fair value at March 31, 2026 and September 30, 2025, respectively)	22,751.7	19,864.1
Broker-dealers, clearing organizations and counterparties (including $5.8 million and $38.4 million at fair value at March 31, 2026 and September 30, 2025, respectively)	1,779.7	963.4
Lenders under loans	564.8	782.0
Senior secured borrowings, net	1,160.3	1,159.0
Income taxes payable	40.4	22.8
Deferred tax liability	106.8	96.9
Collateralized transactions:
Securities sold under agreements to repurchase	17,374.5	13,551.0
Securities loaned	2,273.5	2,550.8
Financial instruments sold, not yet purchased, at fair value	3,789.2	2,919.8
Total liabilities	50,927.6	42,890.6
Commitments and contingencies (Note 11)
Stockholders' equity:
Preferred stock, $0.01 par value. Authorized 1,000,000 shares; no shares issued or outstanding	0.0	0.0
Common stock, $0.01 par value. Authorized 200,000,000 shares; 83,200,883 issued and 79,029,499 outstanding at March 31, 2026 and 82,451,337 issued and 78,279,953 outstanding at September 30, 2025	0.8	0.8
Common stock in treasury, at cost. 4,171,384 shares at March 31, 2026 and September 30, 2025	(32.8)	(32.8)
Additional paid-in-capital	757.3	730.6
Retained earnings	2,008.1	1,694.8
Accumulated other comprehensive loss, net	(34.1)	(16.0)
Total equity	2,699.3	2,377.4
Total liabilities and stockholders' equity	$ 53,626.9	$ 45,268.0

Goodwill - Schedule of Goodwill Allocated to Operating Segments (Details) - USD ($) $ in Millions	Mar. 31, 2026	Sep. 30, 2025
Goodwill [Line Items]
Total Goodwill	$ 301.8	$ 298.3
Commercial
Goodwill [Line Items]
Total Goodwill	115.0	115.6
Institutional
Goodwill [Line Items]
Total Goodwill	162.6	167.0
Self-Directed/Retail
Goodwill [Line Items]
Total Goodwill	6.1	5.7
Payments
Goodwill [Line Items]
Total Goodwill	$ 18.1	$ 10.0

- Definition

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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-Paragraph 24
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- Definition

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+ Details

Commitments and Contingencies (Details) - USD ($) $ in Millions		1 Months Ended
	Mar. 12, 2026	Mar. 31, 2026
Commitments and Contingencies Disclosure [Abstract]
Compensatory damages awarded to the Company	$ 1.0
Compensatory damages awarded to other party	$ 2.9
Payment for arbitration settlement		$ 1.9

Condensed Consolidated Income Statements (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Revenues:
Total revenues	$ 45,760.9	$ 36,890.7	$ 84,790.8	$ 64,826.0
Cost of sales of physical commodities	44,194.1	35,934.7	81,785.8	62,925.7
Operating revenues	1,566.8	956.0	3,005.0	1,900.3
Transaction-based clearing expenses	152.7	91.8	285.3	178.3
Introducing broker commissions	97.4	45.5	190.6	89.8
Interest expense	461.1	316.6	922.8	622.8
Interest expense on corporate funding	26.5	14.8	52.8	30.0
Net operating revenues	829.1	487.3	1,553.5	979.4
Compensation and other expenses:
Compensation and benefits	407.2	267.1	763.1	519.6
Trading systems and market information	25.8	19.5	50.8	39.5
Professional fees	18.4	16.5	51.2	35.5
Non-trading technology and support	28.4	20.9	55.0	40.6
Occupancy and equipment rental	17.9	13.1	34.0	26.1
Selling and marketing	14.0	13.4	28.1	25.4
Travel and business development	16.8	7.1	28.6	15.5
Communications	3.7	2.1	7.4	4.2
Depreciation and amortization	26.9	15.6	51.9	31.3
Bad debts, net of recoveries	12.4	0.1	13.6	1.9
Other	27.8	14.8	54.7	31.5
Total compensation and other expenses	599.3	390.2	1,138.4	771.1
Other (losses)/gains, net	(2.7)	0.0	(3.1)	5.7
Income before tax	227.1	97.1	412.0	214.0
Income tax expense	52.8	25.4	98.7	57.2
Net income	$ 174.3	$ 71.7	$ 313.3	$ 156.8
Earnings per share:
Basic (in dollars per share)	$ 2.21	$ 0.99	$ 3.98	$ 2.17
Diluted (in dollars per share)	$ 2.07	$ 0.94	$ 3.74	$ 2.07
Weighted-average number of common shares outstanding:
Basic (in shares)	76,498,598	70,184,147	76,174,376	69,903,861
Diluted (in shares)	81,456,531	74,064,635	80,956,862	73,472,168
Sales of physical commodities
Revenues:
Total revenues	$ 44,296.9	$ 35,992.6	$ 81,986.0	$ 63,043.7
Principal gains, net
Revenues:
Total revenues	469.7	300.5	848.2	609.4
Commission and clearing fees
Revenues:
Total revenues	347.5	164.3	652.5	313.6
Consulting, management, and account fees
Revenues:
Total revenues	69.0	44.3	145.1	92.1
Interest income
Revenues:
Total revenues	$ 577.8	$ 389.0	$ 1,159.0	$ 767.2

Goodwill

6 Months Ended

Mar. 31, 2026

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill

Goodwill allocated to the Company’s operating segments is as follows:


(in millions)	March 31, 2026		September 30, 2025
Commercial	$	115.0	$	115.6
Institutional	162.6		167.0
Self-Directed/Retail	6.1		5.7
Payments	18.1		10.0
Total Goodwill	$	301.8	$	298.3

The Company recorded additional goodwill and adjustments to goodwill during the six months ended March 31, 2026 related to the purchase price allocation for the following acquisitions, as further discussed in Note 17 (in millions):


Acquisition	Reportable Segment	Goodwill
Intercam Advisors, Inc. and Intercam Securities, Inc.	Self-Directed/Retail	$	0.4
Plantureux et Associés	Commercial	2.9
WCS International Limited	Payments	8.0
R.J. O’Brien & Associates, LLC (1)	Commercial	(3.4)
R.J. O’Brien & Associates, LLC(1)	Institutional	(4.4)
	Total Goodwill Recorded	$	3.5
(1) These amounts represent current period adjustments related to this acquisition, which was completed during the year ended September 30, 2025.

- Definition

The entire disclosure for goodwill.

+ References + Details

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Income Taxes (Details) - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Income Tax Disclosure [Abstract]
Income tax expense	$ 52.8	$ 25.4	$ 98.7	$ 57.2
Effective income tax rate	23.00%	26.00%

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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+ Details

Acquisitions - R.J. O'Brien - Schedule of Operating Revenue and Net Income (Details) - R.J. O’Brien - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2026	Mar. 31, 2026
Business Combination [Line Items]
Operating revenue	$ 213.5	$ 414.5
Net income	$ 20.9	$ 40.3

- Definition

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Reference 32: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
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Reference 34: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Subparagraph (c)
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-Paragraph 1
-Subparagraph (b)(2)
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-URI https://asc.fasb.org/1943274/2147479907/805-20-50-1

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-SubTopic 10
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-Subparagraph (g)(3)
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+ Details

Allowance for Doubtful Accounts

6 Months Ended

Mar. 31, 2026

Receivables [Abstract]

Allowance for Doubtful Accounts

The allowance for doubtful accounts related to receivables from clients was $63.8 million and $53.9 million as of March 31, 2026 and September 30, 2025, respectively. The allowance for doubtful accounts related to deposits with and receivables from broker-dealers, clearing organizations, and counterparties was $0.1 million and $0.0 million as of March 31, 2026 and September 30, 2025, respectively.

Activity in the allowance for doubtful accounts for the six months ended March 31, 2026 was as follows:


(in millions)
Balance as of September 30, 2025	$	53.9
Provision for bad debts(1)	13.7
Allowance charge-offs	(3.5)

Other	(0.2)
Balance as of March 31, 2026	$	63.9
(1) $(0.1) million is included in bad debt expense for the six months ended March 31, 2026 on the Condensed Consolidated Income Statements, which is not included in the allowance.

Other Expenses

6 Months Ended

Mar. 31, 2026

Other Expenses [Abstract]

Other Expenses

Other expenses consisted of the following, for the periods indicated.


	Three Months Ended March 31,				Six Months Ended March 31,
(in millions)	2026		2025		2026		2025
Non-income taxes	$	4.2	$	2.5	$	5.1	$	5.3
Insurance	4.2		2.6		9.0		6.2
Employee related expenses	1.6		1.7		3.7		3.6
Other direct business expenses	8.9		3.9		15.5		7.9
Membership fees	1.4		1.0		2.5		1.9
Director and public company expenses	0.7		0.7		1.2		1.2
Office expenses	1.1		0.6		2.0		1.3
Other expenses	5.7		1.8		15.7		4.1
Total other expenses	$	27.8	$	14.8	$	54.7	$	31.5

Intangible Assets - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of intangible assets	$ 9.7	$ 1.2	$ 17.9	$ 2.3
Write off amortized intangible assets			$ 4.6

- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
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-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

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-Topic 220
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-Paragraph 18
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-Paragraph 2
-Subparagraph (a)(2)
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-Name Accounting Standards Codification
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-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-6

+ Details

Accumulated Other Comprehensive Loss, Net (Tables)

6 Months Ended

Mar. 31, 2026

Equity [Abstract]

Schedule of Changes in Accumulated Other Comprehensive Loss

The following table summarizes the changes in accumulated other comprehensive loss, net for the six months ended March 31, 2026.


(in millions)	Foreign Currency Translation Adjustment		Pension Benefits Adjustment		Cash Flow Hedge		Accumulated Other Comprehensive Loss, net
Balances as of September 30, 2025	$	(21.4)	$	(1.3)	$	6.7	$	(16.0)
Other comprehensive loss, net of tax	0.1		—		(18.2)		(18.1)
Balances as of March 31, 2026	$	(21.3)	$	(1.3)	$	(11.5)	$	(34.1)

Goodwill (Tables)

6 Months Ended

Mar. 31, 2026

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Goodwill

Goodwill allocated to the Company’s operating segments is as follows:


(in millions)	March 31, 2026		September 30, 2025
Commercial	$	115.0	$	115.6
Institutional	162.6		167.0
Self-Directed/Retail	6.1		5.7
Payments	18.1		10.0
Total Goodwill	$	301.8	$	298.3


Acquisition	Reportable Segment	Goodwill
Intercam Advisors, Inc. and Intercam Securities, Inc.	Self-Directed/Retail	$	0.4
Plantureux et Associés	Commercial	2.9
WCS International Limited	Payments	8.0
R.J. O’Brien & Associates, LLC (1)	Commercial	(3.4)
R.J. O’Brien & Associates, LLC(1)	Institutional	(4.4)
	Total Goodwill Recorded	$	3.5
(1) These amounts represent current period adjustments related to this acquisition, which was completed during the year ended September 30, 2025.

- Definition

Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 24
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482548/350-20-55-24

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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-Paragraph 1
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org/1943274/2147482573/350-20-50-1

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
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-SubTopic 20
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-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
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Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section 50
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-URI https://asc.fasb.org/1943274/2147482573/350-20-50-1

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section 50
-Paragraph 1
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Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section 50
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-URI https://asc.fasb.org/1943274/2147482573/350-20-50-1

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482573/350-20-50-1

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org/1943274/2147482573/350-20-50-1

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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-URI https://asc.fasb.org/1943274/2147482573/350-20-50-1A

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482573/350-20-50-2

+ Details

Regulatory Capital Requirements - Narrative (Details) $ in Millions	Mar. 31, 2026 USD ($)
Capital and Other Regulatory Requirements [Abstract]
Adjusted net capital	$ 10.0

Intangible Assets - Schedule of Gross and Net Carrying Values of Intangible Assets (Details) - USD ($) $ in Millions	Mar. 31, 2026	Sep. 30, 2025
Intangible Asset, Acquired, Finite-Lived [Line Items]
Finite-lived intangible assets, gross amount	$ 475.4	$ 458.0
Finite-lived intangible assets, accumulated amortization	(39.3)	(26.1)
Total intangible assets subject to amortization	436.1	431.9
Indefinite-lived intangible assets	5.9	6.0
Intangible assets, gross amount	481.3	464.0
Total intangible assets, net amount	442.0	437.9
Website domains
Intangible Asset, Acquired, Finite-Lived [Line Items]
Indefinite-lived intangible assets	2.2	2.3
Business licenses
Intangible Asset, Acquired, Finite-Lived [Line Items]
Indefinite-lived intangible assets	3.7	3.7
Trade/domain names and other licenses
Intangible Asset, Acquired, Finite-Lived [Line Items]
Finite-lived trade/domain names and other licenses, gross amount	7.1	10.6
Finite-lived intangible assets, accumulated amortization	(3.4)	(4.9)
Total intangible assets subject to amortization	3.7	5.7
Software programs/platforms
Intangible Asset, Acquired, Finite-Lived [Line Items]
Finite-lived software programs/platforms, gross amount	2.4	2.4
Finite-lived intangible assets, accumulated amortization	(2.2)	(2.0)
Total intangible assets subject to amortization	0.2	0.4
Client and supplier base
Intangible Asset, Acquired, Finite-Lived [Line Items]
Finite-lived customer base, gross amount	465.9	445.0
Finite-lived intangible assets, accumulated amortization	(33.7)	(19.2)
Total intangible assets subject to amortization	$ 432.2	$ 425.8

Acquisitions - R.J. O’Brien - Schedule of Unaudited Pro Forma Financial Information (Details) - R.J. O’Brien - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2025	Mar. 31, 2025
Business Combination, Pro Forma Information [Line Items]
Total revenues	$ 37,114.2	$ 65,258.6
Operating revenues	1,179.5	2,332.9
Net income	$ 94.4	$ 173.9
Basic earnings per share (in dollars per share)	$ 1.23	$ 2.27
Diluted earnings per share (in dollars per share)	$ 1.17	$ 2.16

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

Assets and Liabilities, at Fair Value

6 Months Ended

Mar. 31, 2026

Fair Value Disclosures [Abstract]

Assets and Liabilities, at Fair Value

Fair value is defined by U.S. GAAP as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between willing market participants on the measurement date.

Fair value is a market-based measure considered from the perspective of a market participant rather than an entity-specific measure. Even when market assumptions are not readily available, the Company is required to develop a set of assumptions that reflect those that market participants would use in pricing an asset or liability at the measurement date. The Company uses prices and inputs that are current as of the measurement date, including periods of market dislocation. In periods of market dislocation, the observability of prices and inputs may be reduced for many securities. This condition could cause a security to be reclassified to a lower level within the fair value hierarchy.

The Company has designed independent price verification controls to validate relevant prices.

Financial and nonfinancial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). A market is active if there are sufficient transactions on an ongoing basis to provide current pricing information for the asset or liability, pricing information is released publicly, and price quotations do not vary substantially either over time or among market participants. Observable inputs reflect the assumptions market participants would use in pricing the asset or liability developed based on market data obtained from sources independent of the reporting entity.

Relevant guidance requires the Company to consider counterparty credit risk of all parties to outstanding derivative instruments that would be considered by a market participant in the transfer or settlement of such contracts (exit price). The Company’s exposure to credit risk on derivative financial instruments principally relates to the portfolio of over-the-counter (“OTC”) derivative contracts as all exchange-traded contracts held can be settled on an active market with a credit guarantee from the respective exchange. The Company requires each counterparty to deposit margin collateral for all OTC instruments and is also required to deposit margin collateral with counterparties. The Company has assessed the nature of these deposits and used its

discretion to adjust each based on the underlying credit considerations for the counterparty and determined that the collateral deposits minimize the exposure to counterparty credit risk in the evaluation of the fair value of OTC instruments as determined by a market participant.

In accordance with FASB Accounting Standards Codification (“ASC”) 820, Fair Value Measurement, the Company groups its assets and liabilities measured at fair value in three levels based on the markets in which the assets and liabilities are traded and the reliability of the assumptions used to determine fair value. These levels are:

Level 1 - Valuation is based upon unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities. Level 1 consists of financial assets and liabilities whose fair values are estimated using quoted market prices.

Level 2 - Valuation is based upon quoted prices for identical or similar assets or liabilities in markets that are less active, that is, markets in which there are few transactions for the asset or liability that are observable for substantially the full term. Included in Level 2 are those financial assets and liabilities for which fair values are estimated using models or other valuation methodologies. These models are primarily industry-standard models that consider various observable inputs, including time value, yield curve, volatility factors, observable current market and contractual prices for the underlying financial instruments, as well as other relevant economic measures.

Level 3 - Valuation is based on prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity). Level 3 comprises financial assets and liabilities whose fair value is estimated based on internally developed models or methodologies utilizing significant inputs that are not readily observable from objective sources. Level 3 includes contingent liabilities that have been valued using an income approach based upon management developed discounted cash flow projections, which are an unobservable input.

Fair value of financial and nonfinancial assets and liabilities that are carried on the Condensed Consolidated Balance Sheets at fair value on a recurring basis

Cash and cash equivalents reported at fair value on a recurring basis includes certificates of deposit and money market mutual funds, which are stated at cost plus accrued interest, which approximates fair value.

Cash, securities and other assets segregated under federal and other regulations reported at fair value on a recurring basis include the value of pledged investments, primarily U.S. Treasury obligations and commodities warehouse receipts.

Deposits with and receivables from broker-dealers, clearing organizations and counterparties and payable to clients and broker-dealers, clearing organizations and counterparties includes the fair value of pledged investments, primarily U.S. Treasury obligations and foreign government obligations. These balances also include the fair value of exchange-traded options on futures and OTC forwards, swaps and options.

Financial instruments owned and sold, not yet purchased include the fair value of equity securities, which includes common, preferred, and foreign ordinary shares, American Depository Receipts (“ADRs”), Global Depository Receipts (“GDRs”), and exchange-traded funds (“ETFs”), corporate and municipal bonds, U.S. Treasury obligations, U.S. government agency obligations, foreign government obligations, agency mortgage-backed obligations, asset-backed obligations, derivative financial instruments, commodities warehouse receipts, exchange firm common stock, and investments in managed funds. The fair value of exchange firm common stock is determined by quoted market prices.

Cash equivalents, debt and equity securities, commodities warehouse receipts, physical commodities inventory, derivative financial instruments and contingent liabilities are carried at fair value, on a recurring basis, and are classified and disclosed into three levels in the fair value hierarchy.

The following section describes the valuation methodologies used by the Company to measure classes of financial instruments at fair value and specifies the level within the fair value hierarchy where various financial instruments are classified.

The Company uses quoted prices in active markets, where available, and classifies instruments with such quotes within Level 1 of the fair value hierarchy. Examples include U.S. Treasury obligations, foreign government obligations, commodities warehouse receipts, certain equity securities traded in active markets, physical precious metals inventory held by a regulated broker-dealer subsidiary, exchange firm common stock, investments in managed funds, as well as options on futures contracts traded on national exchanges.

When instruments are traded in secondary markets and observable prices are not available for substantially the full term, the Company generally relies on internal valuation techniques based upon observable inputs for comparable financial instruments, or prices obtained from third-party pricing services or brokers or a combination thereof, and accordingly, classifies these instruments as Level 2. Examples include corporate and municipal bonds, U.S. government agency obligations, agency-mortgage backed obligations, asset-backed obligations, certain equity securities traded in less active markets, and OTC

derivative contracts, which include purchase and sale commitments related to the Company’s foreign exchange, agricultural, and energy commodities.

Certain derivatives without a quoted price in an active market and derivatives executed OTC are valued using internal valuation techniques, including pricing models which utilize significant inputs observable to market participants. The valuation techniques and inputs depend on the type of derivative and the nature of the underlying instrument. The key inputs depend upon the type of derivative and the nature of the underlying instrument and include interest yield curves, foreign exchange rates, commodity prices, volatilities and correlations. These derivative instruments are included within Level 2 of the fair value hierarchy.

Physical commodities inventory includes precious metals that are a part of the trading activities of a regulated broker-dealer subsidiary. The physical commodities held by the broker-dealer are recorded at fair value using exchange-quoted prices. Physical commodities inventory also includes agricultural commodities that are a part of the trading activities of a non-broker dealer subsidiary and are recorded at net realizable value using exchange-quoted prices. The fair value of precious metals physical commodities inventory is based upon unadjusted exchange-quoted prices and is, therefore, classified within Level 1 of the fair value hierarchy. The fair value of agricultural physical commodities inventory and the related OTC firm sale and purchase commitments are generally based upon exchange-quoted prices, adjusted for basis or differences in local markets, broker or dealer quotations or market transactions in either listed or OTC markets. Exchange-quoted prices are adjusted for location and quality because the exchange-quoted prices for agricultural and energy related products represent contracts that have standardized terms for commodity, quantity, future delivery period, delivery location, and commodity quality or grade. The basis or local market adjustments are observable inputs or have an insignificant impact on the measurement of fair value and, therefore, the agricultural physical commodities inventory, as well as the related OTC forward firm sale and purchase commitments have been included within Level 2 of the fair value hierarchy.

With the exception of certain derivative instruments where the valuation approach is disclosed above, financial instruments owned and sold are primarily valued using third-party pricing sources. Third-party pricing vendors compile prices from various sources and often apply matrix pricing for similar securities when market-observable transactions for the instruments are not observable for substantially the full term. The Company reviews the pricing methodologies used by third-party pricing vendors in order to evaluate the fair value hierarchy classification of vendor-priced financial instruments and the accuracy of vendor pricing, which typically involves comparing primary vendor prices to internal trader prices or secondary vendor prices. When evaluating the propriety of vendor-priced financial instruments using secondary prices, considerations include the range and quality of vendor prices, level of observable transactions for identical and similar instruments, and judgments based upon knowledge of a particular market and asset class. If the primary vendor price does not represent fair value, justification for using a secondary price, including source data used to make the determination, is subject to review and approval by authorized personnel prior to using a secondary price. Financial instruments owned and sold that are valued using third party pricing sources are included within either Level 1 or Level 2 of the fair value hierarchy based upon the observability of the inputs used and the level of activity in the market.

The fair value estimates presented herein are based on pertinent information available to management as of March 31, 2026 and September 30, 2025 and through the dates of the respective reports. Although management is not aware of any factors that would significantly affect the estimated fair value amounts, such amounts have not been comprehensively revalued for purposes of these condensed consolidated financial statements since that date and current estimates of fair value may differ significantly from the amounts presented herein.


	March 31, 2026
(in millions)	Level 1		Level 2		Level 3		Netting (1)		Total
Assets:
Certificates of deposit	$	26.7	$	—	$	—	$	—	$	26.7
Money market mutual funds and other	153.1		—		—		—		153.1
Cash and cash equivalents	179.8		—		—		—		179.8
Commodities warehouse receipts	21.5		—		—		—		21.5
U.S. government agency obligations	—		110.8		—		—		110.8
U.S. Treasury obligations	985.1		—		—		—		985.1
Securities and other assets segregated under federal and other regulations	1,006.6		110.8		—		—		1,117.4
U.S. Treasury obligations	2,947.6		—		—		—		2,947.6
U.S. government agency obligations	—		1,606.9		—		—		1,606.9
To be announced and forward settling securities	—		167.6		—		(91.1)		76.5
Foreign government obligations	23.4		—		—		—		23.4
Derivatives	6,714.6		1,938.6		—		(8,000.0)		653.2
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	9,685.6		3,713.1		—		(8,091.1)		5,307.6
Receivables from clients, net - Derivatives	606.9		871.2		—		(1,425.7)		52.4
Equity securities	703.1		12.1		—		—		715.2
Corporate and municipal bonds	—		683.6		—		—		683.6
U.S. Treasury obligations	1,614.6		—		—		—		1,614.6
U.S. government agency obligations	—		912.9		—		—		912.9
Foreign government obligations	—		2.5		—		—		2.5
Agency mortgage-backed obligations	—		6,412.3		—		—		6,412.3
Asset-backed obligations	—		185.4		—		—		185.4
Derivatives	—		889.6		—		(594.7)		294.9

Commodities warehouse receipts	346.9		—		—		—		346.9
Exchange firm common stock	50.8		—		—		—		50.8
Cash flow hedges	—		2.2		—		—		2.2
Mutual funds and other	38.3		—		2.3		—		40.6
Financial instruments owned	2,753.7		9,100.6		2.3		(594.7)		11,261.9
Physical commodities inventory	133.4		303.8		—		—		437.2
Total assets at fair value	$	14,366.0	$	14,099.5	$	2.3	$	(10,111.5)	$	18,356.3
Liabilities:
Accounts payable and other accrued liabilities - contingent liabilities	$	—	$	—	$	59.8	$	—	$	59.8
Payables to clients - Derivatives	6,264.6		688.1		—		(6,994.2)		(41.5)
To be announced and forward settling securities	—		99.0		—		(92.0)		7.0
Derivatives	1,001.0		1,431.1		—		(2,433.3)		(1.2)
Payable to broker-dealers, clearing organizations and counterparties	1,001.0		1,530.1		—		(2,525.3)		5.8
Equity securities	473.4		6.2		—		—		479.6

Corporate and municipal bonds	—		240.4		—		—		240.4
U.S. Treasury obligations	2,626.8		—		—		—		2,626.8

Agency mortgage-backed obligations	—		0.1		—		—		0.1

Derivatives	2.2		956.7		—		(529.8)		429.1
Cash flow hedges	—		11.9		—		—		11.9

Other	—		1.2		0.1		—		1.3
Financial instruments sold, not yet purchased	3,102.4		1,216.5		0.1		(529.8)		3,789.2
Total liabilities at fair value	$	10,368.0	$	3,434.7	$	59.9	$	(10,049.3)	$	3,813.3

(1)Represents cash collateral and the impact of netting across each level of the fair value hierarchy.


	September 30, 2025
(in millions)	Level 1		Level 2		Level 3		Netting (1)		Total
Assets:
Certificates of deposit	$	10.3	$	—	$	—	$	—	$	10.3
Money market mutual funds	94.8		—		—		—		94.8
Cash and cash equivalents	105.1		—		—		—		105.1
Commodities warehouse receipts	145.4		—		—		—		145.4
U.S. government agency obligations	—		110.7		—		—		110.7
U.S. Treasury obligations	693.9		—		—		—		693.9
Securities and other assets segregated under federal and other regulations	839.3		110.7		—		—		950.0
U.S. Treasury obligations	5,210.9		—		—		—		5,210.9
U.S. government agency obligations	—		1,103.1		—		—		1,103.1
To be announced and forward settling securities	—		34.9		—		(30.1)		4.8
Foreign government obligations	21.2		—		—		—		21.2
Derivatives	3,208.2		3,508.7		—		(6,614.0)		102.9
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net	8,440.3		4,646.7		—		(6,644.1)		6,442.9
Receivables from clients, net - Derivatives	61.2		506.5				(509.6)		58.1
Equity securities	556.0		6.7		—		—		562.7
Corporate and municipal bonds	—		485.7		—		—		485.7
U.S. Treasury obligations	678.8		—		—		—		678.8
U.S. government agency obligations	—		701.9		—		—		701.9
Foreign government obligations	—		4.1		—		—		4.1
Agency mortgage-backed obligations	—		5,378.9		—		—		5,378.9
Asset-backed obligations	—		373.4		—		—		373.4
Derivatives	—		658.4		—		(468.0)		190.4

Commodities warehouse receipts	144.6		—		—		—		144.6
Exchange firm common stock	47.0		—		—		—		47.0
Cash flow hedges	—		9.5		—		—		9.5
Mutual funds and other	25.1		—		2.3		—		27.4

Financial instruments owned	1,451.5		7,618.6		2.3		(468.0)		8,604.4
Physical commodities inventory	221.8		249.3		—		—		471.1
Total assets at fair value	$	11,119.2	$	13,131.8	$	2.3	$	(7,621.7)	$	16,631.6
Liabilities:
Accounts payable and other accrued liabilities - contingent liabilities	$	—	$	—	$	32.3	$	—	$	32.3
Payables to clients - Derivatives	3,113.1		904.1		—		(3,486.5)		530.7
To be announced and forward settling securities	—		76.0		—		(26.1)		49.9
Derivatives	197.5		3,481.1		—		(3,690.1)		(11.5)
Payable to broker-dealers, clearing organizations and counterparties	197.5		3,557.1		—		(3,716.2)		38.4
Equity securities	367.3		4.4		—		—		371.7

Corporate and municipal bonds	—		264.1		—		—		264.1
U.S. Treasury obligations	1,983.2		—		—		—		1,983.2
U.S. government agency obligations	—		1.3		—		—		1.3
Agency mortgage-backed obligations	—		1.1		—		—		1.1

Derivatives	6.3		682.6		—		(391.6)		297.3
Cash flow hedges	—		1.0		—		—		1.0
Other	—		—		0.1		—		0.1

Financial instruments sold, not yet purchased	2,356.8		954.5		0.1		(391.6)		2,919.8
Total liabilities at fair value	$	5,667.4	$	5,415.7	$	32.4	$	(7,594.3)	$	3,521.2

(1)Represents cash collateral and the impact of netting across each level of the fair value hierarchy.

Realized and unrealized gains and losses are included in Principal gains, net, Interest income, and Cost of sales of physical commodities in the Condensed Consolidated Income Statements.

Additional disclosures about the fair value of financial instruments that are not carried on the Condensed Consolidated Balance Sheets at fair value

Many, but not all, of the financial instruments that the Company holds are recorded at fair value in the Condensed Consolidated Balance Sheets. The following represents financial instruments for which the ending balance at March 31, 2026 and September 30, 2025 was not carried at fair value on the Condensed Consolidated Balance Sheets in accordance with U.S. GAAP:

Short-term financial instruments: The carrying value of short-term financial instruments, including cash and cash equivalents, cash segregated under federal and other regulations, securities purchased under agreements to resell and securities sold under agreements to repurchase, and securities borrowed and loaned are recorded at amounts that approximate the fair value of these instruments due to their short-term nature and level of collateralization. These financial instruments generally expose the Company to limited credit risk and have no stated maturities or have short-term maturities and carry interest rates that approximate market rates. Under the fair value hierarchy, cash and cash equivalents and cash segregated under federal and other regulations are classified as Level 1. Securities purchased under agreements to resell and securities sold under agreements to repurchase, and securities borrowed and loaned are classified as Level 2 under the fair value hierarchy as they are generally overnight, or short-term in nature, and are collateralized by equity securities, U.S. Treasury obligations, U.S. government agency obligations, agency mortgage-backed obligations, and asset-backed obligations.

Receivables and other assets: Receivables from broker-dealers, clearing organizations, and counterparties, receivables from clients, net, notes receivables and certain other assets are recorded at amounts that approximate fair value due to their short-term nature and are classified as Level 2 under the fair value hierarchy.

Payables: Payables to clients and payables to broker-dealers, clearing organizations, and counterparties are recorded at amounts that approximate fair value due to their short-term nature and are classified as Level 2 under the fair value hierarchy.

Lenders under loans: Payables to lenders under loans carry variable rates of interest and thus approximate fair value and are classified as Level 2 under the fair value hierarchy.

Senior secured borrowings, net: Senior secured borrowings, net includes the Company’s 7.875% Senior Secured Notes due 2031 (the “Notes due 2031”) and the Company’s 6.875% Senior Secured Notes due 2032 (the “Notes due 2032”), as further described in Note 9, with carrying values of $544.7 million and $615.6 million, respectively, as of March 31, 2026. The carrying value of the Notes due 2031 and Notes due 2032 represent their principal amount net of unamortized deferred financing costs. As of March 31, 2026, the Notes due 2031 and Notes due 2032 had fair values of $570.9 million and $630.7 million, respectively. They were classified as Level 2 under the fair value hierarchy.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 107
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-107

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2E
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2E

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 940
-SubTopic 820
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478119/940-820-50-1

+ Details

Condensed Consolidated Statements of Cash Flows (Unaudited) (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025
Statement of Cash Flows [Abstract]
Non-cash equivalent segregated assets	$ 821.9	$ 10.2
Segregated cash and other non cash equivalent assets included with in deposits and receivables from broker dealers clearing organizations and counter parties	2,699.7	2,336.9
Non segregated cash and other non cash equivalent assets included with in deposits and receivables from broker dealers clearing organizations and counter parties	$ 4,400.6	$ 3,099.1

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)
$ in Millions

6 Months Ended

Mar. 31, 2026

Mar. 31, 2025

Cash flows from operating activities:

Net income

$ 313.3

$ 156.8

Adjustments to reconcile net income to net cash provided by/(used in) operating activities:

Depreciation and amortization

51.9

31.3

Amortization of right of use assets

10.2

14.6

Bad debts, net of recoveries

13.6

1.9

Deferred income taxes

14.9

15.8

Amortization and extinguishment of debt issuance costs

3.1

2.0

Amortization of share-based compensation expense

28.0

22.0

Loss on disposal of property and equipment

2.5

0.0

Accretion of deferred consideration

4.4

0.0

Adjustment to fair value of deferred consideration

1.1

0.0

Loss on equity method investment

0.6

0.0

Changes in operating assets and liabilities, net:

Securities and other assets segregated under federal and other regulations

(350.9)

41.6

Securities purchased under agreements to resell

(4,875.7)

(1,716.1)

Securities borrowed

453.2

(141.6)

Deposits with and receivables from broker-dealers, clearing organizations, and counterparties, net

677.4

(767.0)

Receivables from clients, net

(79.6)

(343.7)

Income taxes receivable

(23.0)

(28.2)

Financial instruments owned, at fair value

(2,664.8)

(1,429.3)

Physical commodities inventory, net

(121.3)

(113.4)

Other assets

(119.0)

(15.7)

Accounts payable and other accrued liabilities

71.6

24.1

Operating lease liabilities

(10.6)

(11.4)

Payables to clients

2,887.6

366.7

Payables to broker-dealers, clearing organizations, and counterparties

816.2

(155.5)

Income taxes payable

27.5

10.0

Securities sold under agreements to repurchase

3,823.5

2,556.0

Securities loaned

(277.3)

(106.0)

Financial instruments sold, not yet purchased, at fair value

858.5

952.8

Net cash provided by/(used in) operating activities

1,536.9

(632.3)

Cash flows from investing activities:

Cash paid for acquisitions of businesses and assets, net of cash acquired

(5.7)

(13.8)

Purchase of exchange memberships and common stock

(0.1)

0.0

Cost method investment

(5.0)

0.0

Purchases of property and equipment

(36.5)

(28.9)

Net cash used in investing activities

(47.3)

(42.7)

Cash flows from financing activities:

Net change in payables to lenders under loans with maturities 90 days or less

(210.9)

2.1

Repayments of note payable

(6.3)

0.0

Deferred payments on acquisitions

(1.5)

(21.1)

Shares withheld to cover taxes on vesting of equity awards

(9.9)

(4.1)

Exercise of stock options

8.6

4.8

Net cash used in financing activities

(220.0)

(18.3)

Effect of exchange rates on cash, segregated cash, cash equivalents, and segregated cash equivalents

(0.4)

(6.7)

Net increase/(decrease) in cash, segregated cash, cash equivalents, and segregated cash equivalents

1,269.2

(700.0)

Cash, segregated cash, cash equivalents, and segregated cash equivalents at beginning of period

11,520.2

6,672.6

Cash, segregated cash, cash equivalents, and segregated cash equivalents at end of period

12,789.4

5,972.6

Supplemental disclosure of cash flow information:

Cash paid for interest

935.4

635.1

Income taxes paid, net of cash refunds

77.8

57.6

Supplemental disclosure of non-cash investing and financing activities:

Identified intangible assets and goodwill on acquisitions

33.0

11.3

Additional consideration payable related to acquisitions, net

22.7

3.2

Acquisition consideration paid in silver bullion

0.0

12.6

Acquisition of business:

Assets acquired

19.5

29.0

Liabilities assumed

11.6

8.1

Total net assets acquired

7.9

20.9

Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation [Abstract]

Cash and cash equivalents

2,122.6

1,307.3

Cash segregated under federal and other regulations

^[1]

5,376.7

2,840.1

Securities segregated under federal and other regulations

^[2]

295.4

0.0

Cash segregated and deposited with or pledged to exchange-clearing organizations and other futures commission merchants (“FCMs”)

^[3]

4,848.0

1,797.5

Securities segregated and pledged to exchange-clearing organizations

^[4]

146.7

27.7

Total cash, segregated cash, cash equivalents, and segregated cash equivalents shown in the condensed consolidated statements of cash flows

$ 12,789.4

$ 5,972.6

[1]	Represents segregated client cash held at third-party banks included within Cash, securities and other assets segregated under federal and other regulations on the Condensed Consolidated Balance Sheets.
[2]	Represents segregated client United States (“U.S.”) Treasury obligations and U.S. government agency obligations. Excludes segregated commodity warehouse receipts, segregated U.S. Treasury obligations with acquired maturities of greater than 90 days, and other assets, combined totaling $821.9 million and $10.2 million as of March 31, 2026 and 2025, respectively, included within Cash, securities and other assets segregated under federal and other regulations on the Condensed Consolidated Balance Sheets.
[3]	Represents segregated client cash on deposit with, or pledged to, exchange clearing organizations and other FCMs. Excludes non-segregated cash and other assets, combined totaling $2,699.7 million and $2,336.9 million as of March 31, 2026 and 2025, respectively, included within Deposits with and receivables from broker-dealers, clearing organizations, and counterparties, net on the Condensed Consolidated Balance Sheets.
[4]	Represents segregated client U.S. Treasury obligations and U.S. government agency obligations on deposit with, or pledged to, exchange clearing organizations and other FCMs. Excludes segregated securities pledged to exchange-clearing organizations with acquired maturities greater than 90 days and other assets, combined totaling $4,400.6 million and $3,099.1 million as of March 31, 2026 and 2025, respectively, included within Deposits with and receivables from broker-dealers, clearing organizations, and counterparties, net on the Condensed Consolidated Balance Sheets.

Revenue from Contracts with Clients - Schedule of Principal Gains, Net Related To Income and Expense of Dividends (Details) - Equity securities - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Disaggregation of Revenue [Line Items]
Dividend income (expense), net reported within Principal gains, net	$ (0.7)	$ 2.1	$ (0.8)	$ 1.3
Dividend income on long equity positions
Disaggregation of Revenue [Line Items]
Dividend income (expense), net reported within Principal gains, net	34.8	37.3	70.9	72.9
Dividend expense on short equity positions
Disaggregation of Revenue [Line Items]
Dividend income (expense), net reported within Principal gains, net	$ (35.5)	$ (35.2)	$ (71.7)	$ (71.6)

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-5

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 91
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479777/606-10-55-91

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Topic 606
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-Section 55
-Paragraph 91
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479777/606-10-55-91

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Topic 606
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-Name Accounting Standards Codification
-Section 55
-Paragraph 91
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479777/606-10-55-91

Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Topic 606
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-Name Accounting Standards Codification
-Section 55
-Paragraph 91
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479777/606-10-55-91

Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 91
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479777/606-10-55-91

Reference 8: http://www.xbrl.org/2003/role/exampleRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 91
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479777/606-10-55-91

Reference 9: http://www.xbrl.org/2003/role/exampleRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 91
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479777/606-10-55-91

+ Details

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2026	Sep. 30, 2025
Statement of Financial Position [Abstract]
Securities and other assets segregated under federal and other regulations	$ 1,117.4	$ 950.0
Deposits with and receivables from broker-dealers, clearing organizations and counterparties at fair value	5,307.6	6,442.9
Receivables from clients at fair value	52.4	58.1
Financial instruments owned, securities pledged as collateral that can be sold or repledged	2,193.9	1,165.8
Physical commodities inventory at fair value	437.2	471.1
Accounts payable and other accrued liabilities at fair value	59.8	32.3
Payables to client at fair value	(41.5)	530.7
Payables to broker-dealers, clearing organizations and counterparties at fair value	$ 5.8	$ 38.4
Preferred stock - par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock - authorized (in shares)	1,000,000	1,000,000
Preferred stock - issued (in shares)	0	0
Preferred stock - outstanding (in shares)	0	0
Common stock - par value (in dollars per share)	$ 0.01	$ 0.01
Common stock - authorized (in shares)	200,000,000	200,000,000
Common stock - issued (in shares)	83,200,883	82,451,337
Common stock - outstanding (in shares)	79,029,499	78,279,953
Treasury stock - shares (in shares)	4,171,384	4,171,384

Basis of Presentation and Consolidation and Accounting Standards Adopted (Policies)	6 Months Ended
	Mar. 31, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	The accompanying unaudited Condensed Consolidated Balance Sheet as of September 30, 2025, which has been derived from the audited consolidated balance sheet as of September 30, 2025, and the unaudited interim condensed consolidated financial statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and disclosures normally included in annual consolidated financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) have been condensed or omitted pursuant to those rules and regulations. The Company believes that the included disclosures clearly and fairly present the information within. In management’s opinion, all adjustments, generally consisting of normal accruals, considered necessary to fairly present the condensed consolidated financial statements for the interim periods presented have been reflected as required by Rule 10-01 of Regulation S-X. Operating results for interim periods are not necessarily indicative of the results that may be expected for the full year. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and related notes contained in the Company’s Annual Report on Form 10-K for the fiscal year ended September 30, 2025, as filed with the SEC.
Consolidation	These condensed consolidated financial statements include the accounts of StoneX Group Inc. and all entities in which the Company has a controlling financial interest. All material intercompany transactions and balances have been eliminated in consolidation.
Use of Estimates	Preparing condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent liabilities as of the date of the condensed consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. The most significant of these estimates and assumptions in the current year relate to fair value measurements for financial instruments, revenue recognition, valuation of inventories, and income taxes. The Company reviews all significant estimates affecting the financial statements on a recurring basis and makes necessary adjustments to the financial statements presented within this Form 10-Q. Although these and other estimates and assumptions are based on the best available information, actual results could be materially different from estimates. Estimates and assumptions are based on management’s best knowledge of current events and actions the Company may undertake in the future, using information reasonably available to the Company as of March 31, 2026 and through the date of this Form 10-Q.
Accounting Standards Adopted	Accounting Standards Adopted In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2023-07, Improvements to Reportable Segment Disclosures, which requires entities to enhance disclosures regarding segments, including significant segment expenses. The Company adopted ASU No. 2023-07 related to annual disclosure requirements effective with the fiscal 2025 Form 10-K, with newly required annual disclosures being included in Note 22 of the fiscal 2025 Form 10-K. The Company adopted ASU 2023-07 related to interim disclosure requirements effective with the first quarter fiscal 2026 10-Q filing and applied the updated disclosure requirements retrospectively to all periods presented. See Note 18 for more information.
Earnings per Share	The Company presents basic and diluted earnings per share (“EPS”) using the two-class method, which requires all outstanding unvested share-based payment awards that contain rights to non-forfeitable dividends and therefore participate in undistributed earnings with common stockholders be included in computing earnings per share. Under the two-class method, net income is reduced by the amount of dividends declared in the period for each class of common stock and participating security. The remaining undistributed earnings are then allocated to common stock and participating securities, based on their respective rights to receive dividends. Restricted stock awards granted to certain employees and directors contain non-forfeitable rights to dividends at the same rate as common stock and are considered participating securities. Basic EPS has been computed by dividing net income by the weighted-average number of common shares outstanding.
Income Taxes	The income tax provision for interim periods comprises income tax on ordinary income/(loss) at the most recent estimated annual effective income tax rate, adjusted for the income tax effect of discrete items. Management uses an estimated annual effective income tax rate based on the forecasted pretax income/(loss) and statutory tax rates in the various jurisdictions in which the Company operates.

- Definition

Disclosure of accounting policy for income taxes, which may include its accounting policies for recognizing and measuring deferred tax assets and liabilities and related valuation allowances, recognizing investment tax credits, operating loss carryforwards, tax credit carryforwards, and other carryforwards, methodologies for determining its effective income tax rate and the characterization of interest and penalties in the financial statements.

+ References + Details

- Definition

Disclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478671/942-235-S50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-05(b)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477314/942-235-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-12

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
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-Name Accounting Standards Codification
-Section 50
-Paragraph 4
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-URI https://asc.fasb.org/1943274/2147482861/275-10-50-4

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
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-Subparagraph (c)
-SubTopic 10
-Topic 275
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-1

+ Details

Segment Analysis

6 Months Ended

Mar. 31, 2026

Segment Reporting [Abstract]

Segment Analysis

The Company’s operating segments are principally based on the nature of the clients it serves (commercial, institutional, and self-directed/retail), and a fourth operating segment, its payments business. The Company manages its business in this manner due to its large global footprint, in which it has more than 5,400 employees allowing it to serve clients in more than 180 countries.

During the three months ended September 30, 2025, the Company’s acquisition of RJO triggered a reassessment of the financial information reviewed by management. The Company determined the acquired business activities of RJO were similar to its existing businesses, and the reassessment confirmed the current composition of the Company’s operating segments, except for one change resulting in the combination of all physical trading capabilities in precious metals being reported within the Commercial segment. Previously, the Self-Directed/Retail segment contained a portion of our precious metals activities. All segment information has been revised to reflect all precious metals business within the Commercial segment retroactive to October 1, 2024.

The Company’s business activities are managed as operating segments and organized into reportable segments as follows:

Commercial

The Company offers commercial clients a comprehensive array of products and services, including risk management and hedging services, execution and clearing of exchange-traded and OTC products, voice brokerage, market intelligence and physical commodity trading, marketing, procurement, logistics and price management services. The ability to provide these high-value-added products and services, differentiates the Company from its competitors and maximizes the opportunity to retain clients.

Institutional

The Company provides institutional clients with a complete suite of equity trading services to help them find liquidity with best execution, consistent liquidity across a robust array of fixed income products, competitive and efficient clearing and execution in all major futures and securities exchanges globally as well as prime brokerage in equities and major foreign currency pairs and swap transactions. Additionally, the Company operates a comprehensive investment banking platform which provides both investment banking services and equity research.

Self-Directed/Retail

The Company provides self-directed/retail clients around the world access to over 18,000 global financial markets, including spot foreign exchange ("forex"), as well as CFDs, which are investment products with returns linked to the performance of underlying assets. In addition, its independent wealth management business offers a comprehensive product suite to self-directed/retail investors in the U.S.

Payments

The Company provides customized payment, technology, and treasury services to banks and commercial businesses as well as charities and non-governmental organizations and government organizations. The Company provides transparent pricing and offers payments services in more than 180 countries and 140 currencies, which it believes is more than any other payments solution provider.

********

The total revenues reported combine gross revenues from physical contracts for subsidiaries that are not broker-dealers and net revenues for all other businesses. In order to reflect the way that the Company’s management views the results, the table below also reflects the segment contribution to Operating revenues, which is shown on the face of the Condensed Consolidated Income Statements and which is calculated by deducting physical commodities cost of sales from total revenues.

Operating revenues, which are shown on the face of the Condensed Consolidated Income Statements is calculated by deducting physical commodities cost of sales from total revenues.

Net Operating revenues, which are also shown on the face of the Condensed Consolidated Income Statements is calculated by deducting transaction-based clearing expenses, introducing broker commissions, and interest expense from operating revenues.

Net contribution is calculated as net operating revenues less direct variable compensation. Variable compensation paid to risk management consultants and traders generally represents a fixed percentage of revenues generated, and in some cases, revenues generated less transaction-based clearing expenses, base salaries and an overhead allocation.

Segment data includes the profitability measure of net contribution by segment. Net contribution is one of the key measures used by management to assess the performance of each segment and for decisions regarding the allocation of the Company’s resources. Net contribution is calculated as revenue less direct cost of sales, transaction-based clearing expenses, variable compensation, introducing broker commissions, and interest expense. Variable compensation paid to risk management

consultants/traders generally represent a fixed percentage of revenues generated, and in some cases, revenues generated less transaction-based clearing expenses, base salaries and an overhead allocation.

Segment data also includes segment income which is calculated as net contribution less non-variable direct expenses of the segment. These non-variable direct expenses include trader base compensation and benefits, operational employee compensation and benefits, communication and data services, business development, professional fees, bad debt expense and other direct expenses.

Inter-segment revenues, expenses, receivables and payables are eliminated upon consolidation.

Total revenues, operating revenues and net operating revenues shown in the table below as “Corporate” primarily consist of interest income from the Company’s centralized corporate treasury function. In the normal course of operations, the Company operates a centralized corporate treasury function in which it may sweep excess cash from certain subsidiaries, where permitted within regulatory limitations, in exchange for a short-term interest bearing intercompany payable, or provide excess cash to subsidiaries in exchange for a short-term interest bearing intercompany receivable in lieu of the subsidiary borrowing on external credit facilities. The intercompany receivables and payables are eliminated during consolidation.

“Overhead costs and expenses” include costs and expenses of certain shared services such as information technology, accounting and treasury, credit and risk, legal and compliance, and human resources and other activities. These amounts represent the gross overhead costs and expenses, before any allocation of overhead costs to operating segments.

The Company’s Executive Committee functions as the Company’s Chief Operating Decision Maker ("CODM"). The Executive Committee comprises its Executive Vice-Chairman, Chief Executive Officer, President, Chief Financial Officer, Chief Operating Officer, Chief Risk Officer, Chief Governance and Legal Officer, Chief Information Officer, and Chief Executive Officer - Asia Pacific.

The accounting policies of the segments are the same as those described in the summary of significant accounting policies. The CODM uses segment net operating revenues and segment income to manage business operational decisions, including the allocation of financial and employee resources, and to evaluate the performance of each segment by comparing the results of each segment with one another, as well as to internal forecasts.

Information for the reportable segments is shown in accordance with the Segment Reporting Topic of the ASC as follows:


	Three Months Ended March 31, 2026
(in millions)	Commercial		Institutional		Self-Directed / Retail		Payments		Corporate		Eliminations		Total
Non-interest revenues	$	44,646.1	$	372.6	$	98.7	$	55.7	$	10.9	$	(0.9)	$	45,183.1
Interest income	85.7		495.8		7.8		0.3		8.8		(20.6)		577.8
Total revenues	44,731.8		868.4		106.5		56.0		19.7		(21.5)		45,760.9
Cost of sales of physical commodities	44,194.2		—		—		—		(0.1)		—		44,194.1
Operating revenues	537.6		868.4		106.5		56.0		19.8		(21.5)		1,566.8
Transaction-based clearing expenses	41.9		102.3		4.5		2.2		2.7		(0.9)		152.7
Introducing broker commissions	51.7		17.0		27.4		1.3		—		—		97.4
Total interest expense	33.8		433.6		2.2		—		38.6		(20.6)		487.6
Net operating revenues	410.2		315.5		72.4		52.5		(21.5)		—		829.1
Variable compensation and benefits	95.1		114.2		4.3		8.8		26.1		—		248.5
Net contribution	315.1		201.3		68.1		43.7		(47.6)		—		580.6
Fixed compensation and benefits	24.5		36.7		8.6		5.3		83.6		—		158.7
Trading systems and market information	5.5		10.3		3.2		0.2		6.6		—		25.8
Professional fees	1.6		3.0		1.5		1.0		11.3		—		18.4
Non-trading technology and support	0.6		1.2		2.1		0.4		24.1		—		28.4
Selling and marketing	1.8		1.2		8.6		0.1		2.3		—		14.0
Travel and business development	2.7		2.8		0.5		0.2		10.6		—		16.8
Depreciation and amortization	6.1		5.5		3.8		1.3		10.2		—		26.9
Bad debts, net of recoveries	10.4		1.5		0.5		—		—		—		12.4
Shared services	11.8		7.0		3.7		2.5		(25.0)		—		—
Other fixed expenses	5.8		8.7		5.4		0.7		28.8		—		49.4
Non-variable expenses	70.8		77.9		37.9		11.7		152.5		—		350.8
Other losses	—		(2.5)		—		(0.2)		—		—		(2.7)
Segment income	$	244.3	$	120.9	$	30.2	$	31.8	$	(200.1)	$	—	$	227.1


	Three Months Ended March 31, 2025
(in millions)	Commercial		Institutional		Self-Directed / Retail		Payments		Corporate		Eliminations		Total
Non-interest revenues	$	36,138.4	$	223.8	$	84.6	$	49.8	$	5.9	$	(0.8)	$	36,501.7
Interest income	46.1		337.4		7.6		0.5		10.8		(13.4)		389.0
Total revenues	36,184.5		561.2		92.2		50.3		16.7		(14.2)		36,890.7
Cost of sales of physical commodities	35,934.7		—		—		—		—		—		35,934.7
Operating revenues	249.8		561.2		92.2		50.3		16.7		(14.2)		956.0
Transaction-based clearing expenses	19.1		67.1		3.2		1.7		1.5		(0.8)		91.8
Introducing broker commissions	13.1		7.2		24.2		1.0		—		—		45.5
Total interest expense	23.3		295.9		1.8		—		23.8		(13.4)		331.4
Net operating revenues	194.3		191.0		63.0		47.6		(8.6)		—		487.3
Variable compensation and benefits	53.4		62.5		4.6		8.8		17.4		—		146.7
Net contribution	140.9		128.5		58.4		38.8		(26.0)		—		340.6
Fixed compensation and benefits	19.8		21.8		8.8		7.4		62.6		—		120.4
Trading systems and market information	4.7		7.7		3.3		0.3		3.5		—		19.5
Professional fees	1.9		1.9		2.8		1.2		8.7		—		16.5
Non-trading technology and support	0.4		1.0		2.6		0.5		16.4		—		20.9
Selling and marketing	1.2		0.8		8.9		0.2		2.3		—		13.4
Travel and business development	2.0		1.9		0.5		0.3		2.4		—		7.1
Depreciation and amortization	2.1		1.0		4.3		1.2		7.0		—		15.6
Bad debts, net of recoveries	(0.3)		(0.1)		0.6		(0.1)		—		—		0.1
Shared services	7.0		3.5		2.3		2.1		(14.9)		—		—
Other fixed expenses	4.9		2.5		2.8		1.2		18.6		—		30.0
Non-variable expenses	43.7		42.0		36.9		14.3		106.6		—		243.5

Segment income	$	97.2	$	86.5	$	21.5	$	24.5	$	(132.6)	$	—	$	97.1


	Six Months Ended March 31, 2026
(in millions)	Commercial		Institutional		Self-Directed / Retail		Payments		Corporate		Eliminations		Total
Non-interest revenues	$	82,585.2	$	737.3	$	185.6	$	112.4	$	13.0	$	(1.7)	$	83,631.8
Interest income	165.6		997.1		15.3		0.6		18.9		(38.5)		1,159.0
Total revenues	82,750.8		1,734.4		200.9		113.0		31.9		(40.2)		84,790.8
Cost of sales of physical commodities	81,785.8		—		—		—		—		—		81,785.8
Operating revenues	965.0		1,734.4		200.9		113.0		31.9		(40.2)		3,005.0
Transaction-based clearing expenses	72.2		197.6		8.1		4.2		4.9		(1.7)		285.3
Introducing broker commissions	101.6		31.7		54.8		2.3		0.2		—		190.6
Total interest expense	64.7		865.4		4.3		—		79.7		(38.5)		975.6
Net operating revenues	726.5		639.7		133.7		106.5		(52.9)		—		1,553.5
Variable compensation and benefits	176.2		221.5		9.4		17.4		39.9		—		464.4
Net contribution	550.3		418.2		124.3		89.1		(92.8)		—		1,089.1
Fixed compensation and benefits	47.0		63.1		15.9		10.2		162.5		—		298.7
Trading systems and market information	10.2		21.8		6.1		0.4		12.3		—		50.8
Professional fees	4.0		18.2		3.4		1.4		24.2		—		51.2
Non-trading technology and support	1.1		2.7		3.7		0.7		46.8		—		55.0
Selling and marketing	2.6		2.5		16.9		0.2		5.9		—		28.1
Travel and business development	5.9		6.1		1.0		0.5		15.1		—		28.6
Depreciation and amortization	11.6		10.9		6.8		2.6		20.0		—		51.9
Bad debts, net of recoveries	11.4		1.6		0.6		—		—		—		13.6
Shared services	21.1		13.7		6.9		5.4		(47.1)		—		—
Other fixed expenses	12.0		14.9		14.5		1.4		53.3		—		96.1
Non-variable expenses	126.9		155.5		75.8		22.8		293.0		—		674.0
Other losses	—		(2.5)		—		(0.6)		—		—		(3.1)
Segment income	$	423.4	$	260.2	$	48.5	$	65.7	$	(385.8)	$	—	$	412.0

	As of March 31, 2026
Total assets	$	10,896.2	$	38,787.2	$	1,342.2	$	606.1	$	1,995.2	$	—	$	53,626.9


	Six Months Ended March 31, 2025
(in millions)	Commercial		Institutional		Self-Directed / Retail		Payments		Corporate		Eliminations		Total
Non-interest revenues	$	63,310.9	$	438.4	$	197.9	$	107.3	$	5.9	$	(1.6)	$	64,058.8
Interest income	99.4		662.4		15.9		1.1		21.9		(33.5)		767.2
Total revenues	63,410.3		1,100.8		213.8		108.4		27.8		(35.1)		64,826.0
Cost of sales of physical commodities	62,925.7		—		—		—		—		—		62,925.7
Operating revenues	484.6		1,100.8		213.8		108.4		27.8		(35.1)		1,900.3
Transaction-based clearing expenses	36.7		130.1		6.6		3.5		3.0		(1.6)		178.3
Introducing broker commissions	24.4		15.3		48.2		1.9		—		—		89.8
Total interest expense	37.7		590.4		3.7		—		54.5		(33.5)		652.8
Net operating revenues	385.8		365.0		155.3		103.0		(29.7)		—		979.4
Variable compensation and benefits	97.1		118.7		7.4		17.9		38.9		—		280.0
Net contribution	288.7		246.3		147.9		85.1		(68.6)		—		699.4
Fixed compensation and benefits	36.9		40.4		18.1		14.0		130.2		—		239.6
Trading systems and market information	8.7		15.6		6.8		0.7		7.7		—		39.5
Professional fees	4.0		6.6		5.4		1.9		17.6		—		35.5
Non-trading technology and support	0.8		1.9		4.7		1.0		32.2		—		40.6
Selling and marketing	2.5		1.8		17.6		0.3		3.2		—		25.4
Travel and business development	4.3		4.3		1.1		0.6		5.2		—		15.5
Depreciation and amortization	3.9		2.0		9.6		2.2		13.6		—		31.3
Bad debts, net of recoveries	0.9		(0.1)		1.1		—		—		—		1.9
Shared services	13.8		6.9		5.4		4.2		(30.3)		—		—
Other fixed expenses	11.6		3.6		6.0		1.6		39.0		—		61.8
Non-variable expenses	87.4		83.0		75.8		26.5		218.4		—		491.1
Other gains, net	—		1.3		4.4		—		—		—		5.7
Segment income	$	201.3	$	164.6	$	76.5	$	58.6	$	(287.0)	$	—	$	214.0

	As of September 30, 2025
Total assets	$	9,826.3	$	32,465.5	$	1,256.2	$	722.5	$	997.5	$	—	$	45,268.0

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-21

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
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-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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+ Details

Securities and Commodity Financing Transactions

6 Months Ended

Mar. 31, 2026

Broker-Dealer [Abstract]

Securities and Commodity Financing Transactions

The Company’s repurchase agreements and securities borrowing and lending arrangements are generally recorded at cost in the Condensed Consolidated Balance Sheets, which is a reasonable approximation of their fair values due to their short-term nature. Secured borrowing and lending arrangements are entered into to obtain collateral necessary to effect settlement, finance inventory positions, meet customer needs or re-lend as part of our dealer operations. The fair value of securities loaned and borrowed is monitored daily compared with the related payable or receivable, and additional collateral or returning excess collateral is requested, as appropriate. These arrangements may serve to limit credit risk resulting from transactions with counterparties. Financial instruments are pledged as collateral under repurchase agreements, securities lending agreements and other secured arrangements, including clearing arrangements. Agreements with counterparties generally contain contractual provisions allowing counterparties the right to sell or repledge collateral. Either the Company or its counterparties may require additional collateral. All collateral is held by the Company or a custodian.

The following tables set forth the carrying value of repurchase agreements, and securities lending agreements by remaining contractual maturity (in millions):


	March 31, 2026
	Overnight and Open		Less than 30 Days		30-90 Days		Over 90 Days		Total
Securities sold under agreements to repurchase	$	30,726.8	$	3,296.9	$	782.4	$	143.4	$	34,949.5
Securities loaned	2,273.5		—		—		—		2,273.5
Gross amount of secured financing	$	33,000.3	$	3,296.9	$	782.4	$	143.4	$	37,223.0


	September 30, 2025
	Overnight and Open		Less than 30 Days		30-90 Days		Over 90 Days		Total
Securities sold under agreements to repurchase	$	26,173.4	$	3,128.5	$	180.4	$	41.4	$	29,523.7
Securities loaned	2,550.8		—		—		—		2,550.8
Gross amount of secured financing	$	28,724.2	$	3,128.5	$	180.4	$	41.4	$	32,074.5

Offsetting of Collateralized Transactions

The following table sets forth the carrying value of repurchase agreements and securities lending agreements by class of collateral pledged (in millions):


Securities sold under agreements to repurchase	March 31, 2026		September 30, 2025
U.S. Treasury obligations	$	19,525.0	$	19,311.9
U.S. government agency obligations and municipal bonds	1,680.9		804.3
Asset-backed obligations	423.7		55.0
Agency mortgage-backed obligations	10,208.6		7,521.4
Foreign government obligations	1,400.9		881.4
Corporate bonds	1,710.4		949.7
Total securities sold under agreement to repurchase	$	34,949.5	$	29,523.7

Securities loaned
Equity securities	$	2,273.5	$	2,550.8
Total securities loaned	2,273.5		2,550.8
Gross amount of secured financing	$	37,223.0	$	32,074.5


	March 31, 2026
Offsetting of collateralized transactions:	Gross Amounts Recognized		Amounts Offset in the Condensed Consolidated Balance Sheet		Net Amounts Presented in the Condensed Consolidated Balance Sheet
Securities purchased under agreements to resell	$	32,776.1	$	(17,575.0)	$	15,201.1
Securities borrowed	$	2,289.9	$	—	$	2,289.9
Securities sold under agreements to repurchase	$	34,949.5	$	(17,575.0)	$	17,374.5
Securities loaned	$	2,273.5	$	—	$	2,273.5


	September 30, 2025
Offsetting of collateralized transactions:	Gross Amounts Recognized		Amounts Offset in the Condensed Consolidated Balance Sheet		Net Amounts Presented in the Condensed Consolidated Balance Sheet
Securities purchased under agreements to resell	$	26,298.1	$	(15,972.7)	$	10,325.4
Securities borrowed	$	2,743.1	$	—	$	2,743.1
Securities sold under agreements to repurchase	$	29,523.7	$	(15,972.7)	$	13,551.0
Securities loaned	$	2,550.8	$	—	$	2,550.8

The Company pledges securities owned as collateral in both tri-party and bilateral arrangements. Pledged securities under tri-party arrangements may not be repledged or sold by the Company’s counterparties, whereas bilaterally pledged securities may be. The approximate fair value of pledged securities that can be sold or repledged by the Company’s counterparties has been parenthetically disclosed on the Condensed Consolidated Balance Sheets.

The Company receives securities as collateral under reverse repurchase agreements, securities borrowed agreements, and margin securities held on behalf of counterparties. This collateral is used by the Company to cover financial instruments sold, not yet purchased; to obtain financing in the form of repurchase agreements; and to meet counterparties’ needs under lending arrangements and matched-book trading strategies. Additional securities collateral is obtained as necessary to ensure such transactions are adequately collateralized. In many instances, the Company is permitted by contract to repledge the securities received as collateral, which may include pledges to cover collateral requirements for tri-party repurchase agreements.

The following table sets forth the fair values, which approximate carrying value because of the short-term nature of collateral pledged, received and repledged (in millions):


	March 31, 2026		September 30, 2025
Securities pledged or repledged to cover collateral requirements for tri-party arrangements	$	11,975.1	$	9,757.7
Securities pledged as collateral that are subject to segregation rules	$	249.0	$	—
Securities received as collateral that may be repledged	$	35,948.4	$	32,452.0
Securities received as collateral that are subject to segregation rules	$	3,774.8	$	1,739.3
Securities received as collateral that may be repledged covering securities sold short	$	3,114.4	$	1,965.1
Repledged securities borrowed and client securities held under custodial clearing arrangements to collateralize securities loaned agreements	$	2,322.8	$	2,491.4

Insider Trading Arrangements

3 Months Ended

Mar. 31, 2026

Trading Arrangements, by Individual

Material Terms of Trading Arrangement

Name and Title

Type of Plan

Adoption Date

Duration or End Date

Aggregate Number of Securities to be Sold

Description of Trading Arrangement

Diego Rotsztain - Chief Governance and Legal Officer

Rule 10b5-1 trading arrangement

2/10/2026

6/8/2026 - 12/4/2026

8,856 shares, 67,500 options

Sales of shares, and exercise of stock options and sale of underlying shares

Mark Maurer - Chief Risk Officer

Rule 10b5-1 trading arrangement

2/12/2026

5/14/2026 - 12/4/2026

185,000 options

Exercise of stock options and sale of underlying shares

William Dunaway - Chief Financial Officer

Rule 10b5-1 trading arrangement

2/13/2026

5/15/2026 - 12/4/2026

225,000 options

Exercise of stock options and sale of underlying shares

Abbey Perkins - Chief Information Officer

Rule 10b5-1 trading arrangement

2/13/2026

6/8/2026 - 12/4/2026

7,930 shares, 8,875 options

Sales of shares, and exercise of stock options and sale of underlying shares

Sean O’Connor - Executive Vice-Chairman

Rule 10b5-1 trading arrangement

2/13/2026

5/15/2026 - 12/4/2026

370,000 options

Exercise of stock options and sale of underlying shares

Non-Rule 10b5-1 Arrangement Adopted

false

Rule 10b5-1 Arrangement Terminated

false

Non-Rule 10b5-1 Arrangement Terminated

false

Diego Rotsztain [Member]

Trading Arrangements, by Individual

Name

Diego Rotsztain

Title

Chief Governance and Legal Officer

Rule 10b5-1 Arrangement Adopted

true

2/10/2026

12/4/2026

297 days

Trading Arrangements, by Individual

Name

Mark Maurer

Title

Chief Risk Officer

Rule 10b5-1 Arrangement Adopted

true

Adoption Date

2/12/2026

Expiration Date

12/4/2026

Arrangement Duration

295 days

William Dunaway [Member]

Trading Arrangements, by Individual

Name

William Dunaway

Title

Chief Financial Officer

Rule 10b5-1 Arrangement Adopted

true

Adoption Date

2/13/2026

Expiration Date

12/4/2026

Arrangement Duration

294 days

Abbey Perkins [Member]

Trading Arrangements, by Individual

Name

Abbey Perkins

Title

Chief Information Officer

Rule 10b5-1 Arrangement Adopted

true

Adoption Date

2/13/2026

Expiration Date

12/4/2026

Arrangement Duration

294 days

Sean O’Connor [Member]

Trading Arrangements, by Individual

Name

Sean O’Connor

Title

Executive Vice-Chairman

Rule 10b5-1 Arrangement Adopted

true

Adoption Date

2/13/2026

Expiration Date

12/4/2026

Arrangement Duration

294 days

Diego Rotsztain Trading Arrangement, Common Stock [Member] | Diego Rotsztain [Member]

Trading Arrangements, by Individual

Aggregate Available

8,856

Diego Rotsztain Trading Arrangement, Stock Options [Member] | Diego Rotsztain [Member]

Trading Arrangements, by Individual

Aggregate Available

67,500

Mark Mauer Trading Arrangement, Stock Options [Member] | Mark Maurer [Member]

Trading Arrangements, by Individual

Aggregate Available

185,000

William Dunaway Trading Arrangement, Stock Options [Member] | William Dunaway [Member]

Trading Arrangements, by Individual

Aggregate Available

225,000

Abbey Perkins Trading Arrangement, Common Stock [Member] | Abbey Perkins [Member]

Trading Arrangements, by Individual

Aggregate Available

7,930

Abbey Perkins Trading Arrangement, Stock Options [Member] | Abbey Perkins [Member]

Trading Arrangements, by Individual

Aggregate Available

8,875

Sean O’Connor Trading Arrangement, Stock Options [Member] | Sean O’Connor [Member]

Trading Arrangements, by Individual

Aggregate Available

370,000

Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Statement of Comprehensive Income [Abstract]
Net income	$ 174.3	$ 71.7	$ 313.3	$ 156.8
Other comprehensive (loss)/gain, net of tax:
Foreign currency translation adjustment	0.6	12.0	0.1	(6.3)
Cash flow hedges	(15.5)	6.6	(18.2)	(0.3)
Total other comprehensive (loss)/gain, net of tax	(14.9)	18.6	(18.1)	(6.6)
Comprehensive income	$ 159.4	$ 90.3	$ 295.2	$ 150.2

- Definition

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References + Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Acquisitions - Narrative (Details) - USD ($) $ in Millions						3 Months Ended		6 Months Ended
Acquisitions - Narrative (Details) - USD ($) $ in Millions	Mar. 23, 2026	Oct. 31, 2025	Oct. 17, 2025	Oct. 07, 2025	Apr. 14, 2025	Dec. 31, 2025	Mar. 31, 2025	Mar. 31, 2025	Mar. 31, 2026	Sep. 30, 2025
Business Combination [Line Items]
Goodwill									$ 301.8	$ 298.3
WCS International Limited
Business Combination [Line Items]
Cash consideration paid	$ 8.6
Deferred consideration	4.2
Goodwill	$ 8.0
Intercam Advisors, Inc. and Intercam Securities, Inc.
Business Combination [Line Items]
Cash consideration paid			$ 1.7
Deferred consideration			0.8
Goodwill			$ 0.4
Plantureux
Business Combination [Line Items]
Cash consideration paid		$ 2.8
Deferred consideration		1.2
Goodwill		$ 2.9
GEA
Business Combination [Line Items]
Cash consideration paid				$ 5.2
Deferred consideration				16.5
Total fair value of intangible assets acquired				$ 21.7
R.J. O’Brien
Business Combination [Line Items]
Cash consideration paid					$ 651.9
Goodwill					166.6
Total fair value of intangible assets acquired					$ 410.6
Percentage of stock purchased					100.00%
Net income (loss)							$ 94.4	$ 173.9
R.J. O’Brien \| Business Combination, Pro Forma Information, Nonrecurring Adjustment, Unrealized Gain (Loss) on Investments
Business Combination [Line Items]
Net income (loss)						$ (4.0)	$ 14.2

Physical Commodities Inventory (Tables)

6 Months Ended

Mar. 31, 2026

Inventory Disclosure [Abstract]

Schedule of Inventory

The Company’s inventories consist of physical commodities as shown below:


(in millions)	March 31, 2026		September 30, 2025
Physical Agriculture and Energy	$	303.8	$	249.3
Precious metals - held by broker-dealer subsidiary	133.4		221.8
Precious metals - held by non-broker-dealer subsidiaries(1)	601.6		446.4
Physical commodities inventory, net	$	1,038.8	$	917.5
(1)Includes raw materials of $2.4 million and work in process of $148.4 million as of March 31, 2026

Revenue from Contracts with Clients - Schedule of Revenue from Contracts with Clients (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	$ 1,382.7	$ 820.4	$ 2,583.2	$ 1,483.5
Principal gains, net	469.7	300.5	848.2	609.4
Interest income	577.8	389.0	1,159.0	767.2
Total revenues	45,760.9	36,890.7	84,790.8	64,826.0
Total operating revenues	1,566.8	956.0	3,005.0	1,900.3
United States
Disaggregation of Revenue [Line Items]
Total revenues	2,749.0	1,880.0	4,992.6	3,664.4
Total operating revenues	1,087.4	728.6	2,095.8	1,364.0
Europe
Disaggregation of Revenue [Line Items]
Total revenues	1,416.6	840.2	2,580.9	1,546.0
Total operating revenues	297.6	102.7	537.7	308.9
South America
Disaggregation of Revenue [Line Items]
Total revenues	183.4	141.7	379.1	305.0
Total operating revenues	53.5	53.8	87.9	85.0
Middle East and Asia
Disaggregation of Revenue [Line Items]
Total revenues	41,397.7	34,024.2	76,739.7	59,314.9
Total operating revenues	114.2	59.6	222.9	120.9
Other
Disaggregation of Revenue [Line Items]
Total revenues	14.2	4.6	98.5	(4.3)
Total operating revenues	14.1	11.3	60.7	21.5
Point-in-time
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	1,339.3	777.9	2,492.5	1,398.6
Time elapsed
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	43.4	42.5	90.7	84.9
Exchange-traded futures and options
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	188.9	71.0	361.1	134.2
OTC derivative brokerage
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	1.6	2.5	4.8	5.3
Equities and fixed income
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	40.0	15.0	74.3	30.1
Mutual funds
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	1.0	0.8	1.8	1.6
Insurance and annuity products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	4.1	3.3	7.5	6.5
Other
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0.8	0.4	0.9	0.8
Total sales-based commission
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	236.4	93.0	450.4	178.5
Mutual funds
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	3.6	3.5	7.2	6.9
Insurance and annuity products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	4.3	4.0	8.3	8.0
Total trailing commission
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	7.9	7.5	15.5	14.9
Clearing fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	97.8	48.0	176.8	92.1
Trade conversion fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	3.8	3.4	6.1	5.6
Other
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	1.6	12.4	3.7	22.5
Total commission and clearing fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	347.5	164.3	652.5	313.6
Total revenues	347.5	164.3	652.5	313.6
Underwriting fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	8.6	0.2	20.5	0.5
Asset management fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	15.9	14.4	32.1	29.2
Advisory and consulting fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	10.0	9.2	22.9	17.8
Sweep program fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	9.6	11.4	20.2	23.0
Client account fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	18.2	6.5	39.7	12.7
Other
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	6.7	2.6	9.7	8.9
Total consulting, management, and account fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	69.0	44.3	145.1	92.1
Total revenues	69.0	44.3	145.1	92.1
Precious metals sales under ASC Topic 606
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	966.2	611.8	1,785.6	1,077.8
Physical precious metals under ASC Topic 815
Disaggregation of Revenue [Line Items]
Sales of physical commodities	41,949.4	34,233.2	77,631.8	59,755.6
Physical agricultural and energy products
Disaggregation of Revenue [Line Items]
Sales of physical commodities	$ 1,381.3	$ 1,147.6	$ 2,568.6	$ 2,210.3
Revenue from Contract with Customer Benchmark \| Customer Concentration Risk \| Clients
Disaggregation of Revenue [Line Items]
Revenues from contracts with clients as a percentage of total revenues	3.00%	2.20%	3.00%	2.30%

Allowance for Doubtful Accounts - Schedule of Allowance for Doubtful Accounts (Details) $ in Millions	6 Months Ended
	Mar. 31, 2026 USD ($)
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance as of September 30, 2025	$ 53.9
Provision for bad debts	13.7
Allowance charge-offs	(3.5)
Other	(0.2)
Balance as of March 31, 2026	63.9
Bad debt expense (reversal)	$ (0.1)

Securities and Commodity Financing Transactions - Schedule of Fair Values of Collateral Pledged, Received and Repledged (Details) - USD ($) $ in Millions	Mar. 31, 2026	Sep. 30, 2025
Assets Sold under Agreements to Repurchase [Line Items]
Securities pledged or repledged to cover collateral requirements for tri-party arrangements	$ 11,261.9	$ 8,604.4
Securities received as collateral that may be repledged	35,948.4	32,452.0
Securities received as collateral that are subject to segregation rules	3,774.8	1,739.3
Securities received as collateral that may be repledged covering securities sold short	3,114.4	1,965.1
Asset Pledged as Collateral with Right
Assets Sold under Agreements to Repurchase [Line Items]
Securities received as collateral that are subject to segregation rules	249.0	0.0
Repledged securities borrowed and client securities held under custodial clearing arrangements to collateralize securities loaned agreements	2,322.8	2,491.4
Tri-party Repurchase Agreements
Assets Sold under Agreements to Repurchase [Line Items]
Securities pledged or repledged to cover collateral requirements for tri-party arrangements	$ 11,975.1	$ 9,757.7

Revenue from Contracts with Clients

6 Months Ended

Mar. 31, 2026

Revenue from Contract with Customer [Abstract]

Revenue from Contracts with Clients

The Company accounts for revenue earned from contracts with clients for services such as the execution, clearing, brokering, and custody of futures and options on futures contracts, OTC derivatives, and securities, investment management, and

underwriting services in accordance with FASB ASC 606, Revenues from Contracts with Customers (“Topic 606”). Revenues for these services are recognized when the performance obligations related to the underlying transaction are completed.

Revenues are recognized when control of the promised goods or services is transferred to clients, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those goods or services. Revenues are analyzed to determine whether the Company is the principal (i.e., reports revenue on a gross basis) or agent (i.e., reports revenues on a net basis) in the contract. Principal or agent designations depend primarily on the control an entity has over the good or service before control is transferred to a client. The indicators of which party exercises control include primary responsibility over performance obligations, inventory risk before the good or service is transferred, and discretion in establishing the price.

Topic 606 does not apply to revenues associated with dealing, or market-making, activities in financial instruments or contracts in the capacity of a principal, including derivative sales contracts which result in physical settlement and interest income.

Revenues within the scope of Topic 606 are presented within Commission and clearing fees; Consulting, management, and account fees; and Sales of physical commodities on the Condensed Consolidated Income Statements. Revenues that are not within the scope of Topic 606 are presented within Sales of physical commodities, Principal gains, net, and Interest income on the Condensed Consolidated Income Statements.


	Three Months Ended March 31,				Six Months Ended March 31,
(in millions)	2026		2025		2026		2025
Revenues from contracts with clients as a percentage of total revenues	3.0	%	2.2	%	3.0	%	2.3	%

The following table represents a disaggregation of the Company’s total revenues separated between revenues from contracts with clients and other sources of revenue for the periods indicated.


	Three Months Ended March 31,				Six Months Ended March 31,
(in millions)	2026		2025		2026		2025
Revenues from contracts with clients:
Commission and clearing fees:
Sales-based:
Exchange-traded futures and options	$	188.9	$	71.0	$	361.1	$	134.2
OTC derivative brokerage	1.6		2.5		4.8		5.3
Equities and fixed income	40.0		15.0		74.3		30.1
Mutual funds	1.0		0.8		1.8		1.6
Insurance and annuity products	4.1		3.3		7.5		6.5
Other	0.8		0.4		0.9		0.8
Total sales-based commission	236.4		93.0		450.4		178.5
Trailing:
Mutual funds	3.6		3.5		7.2		6.9
Insurance and annuity products	4.3		4.0		8.3		8.0
Total trailing commission	7.9		7.5		15.5		14.9

Clearing fees	97.8		48.0		176.8		92.1
Trade conversion fees	3.8		3.4		6.1		5.6
Other	1.6		12.4		3.7		22.5
Total commission and clearing fees	347.5		164.3		652.5		313.6
Consulting, management, and account fees:
Underwriting fees	8.6		0.2		20.5		0.5
Asset management fees	15.9		14.4		32.1		29.2
Advisory and consulting fees	10.0		9.2		22.9		17.8
Sweep program fees	9.6		11.4		20.2		23.0
Client account fees	18.2		6.5		39.7		12.7
Other	6.7		2.6		9.7		8.9
Total consulting, management, and account fees	69.0		44.3		145.1		92.1
Sales of physical commodities:
Precious metals sales under ASC Topic 606	966.2		611.8		1,785.6		1,077.8
Total revenues from contracts with clients	$	1,382.7	$	820.4	$	2,583.2	$	1,483.5

Method of revenue recognition:
Point-in-time	$	1,339.3	$	777.9	$	2,492.5	$	1,398.6
Time elapsed	43.4		42.5		90.7		84.9
Total revenues from contracts with clients	1,382.7		820.4		2,583.2		1,483.5
Other sources of revenues
Physical precious metals under ASC Topic 815	41,949.4		34,233.2		77,631.8		59,755.6
Physical agricultural and energy products	1,381.3		1,147.6		2,568.6		2,210.3
Principal gains, net	469.7		300.5		848.2		609.4
Interest income	577.8		389.0		1,159.0		767.2
Total revenues	$	45,760.9	$	36,890.7	$	84,790.8	$	64,826.0

Total revenues by primary geographic region:
United States	$	2,749.0	$	1,880.0	$	4,992.6	$	3,664.4
Europe	1,416.6		840.2		2,580.9		1,546.0
South America	183.4		141.7		379.1		305.0
Middle East and Asia	41,397.7		34,024.2		76,739.7		59,314.9
Other	14.2		4.6		98.5		(4.3)
Total revenues	$	45,760.9	$	36,890.7	$	84,790.8	$	64,826.0

Operating revenues by primary geographic region:
United States	$	1,087.4	$	728.6	$	2,095.8	$	1,364.0
Europe	297.6		102.7		537.7		308.9
South America	53.5		53.8		87.9		85.0
Middle East and Asia	114.2		59.6		222.9		120.9
Other	14.1		11.3		60.7		21.5
Total operating revenues	$	1,566.8	$	956.0	$	3,005.0	$	1,900.3

The substantial majority of the Company’s performance obligations for revenues from contracts with clients are satisfied at a point in time and are typically collected from clients by debiting their accounts with the Company.

Commission and clearing fees revenue and Consulting, management, and account fees revenue are primarily related to the Commercial, Institutional and Self-Directed/Retail reportable segments. Sales of physical commodities under Topic 606 are related to the Company’s Commercial segment. Principal gains, net are contributed by all of the Company’s reportable segments. Interest income is primarily related to the Commercial and Institutional reportable segments. Precious metals trading and agricultural and energy product trading revenues are related to the Commercial reportable segment. Precious metals sales that are recognized on a point-in-time basis are included in the Commercial reportable segment.

Principal gains, net also includes dividend income on long equity positions and dividend expense on short equity positions, which are recognized on the ex-dividend date. The following table indicates the relevant income and expense:


	Three Months Ended March 31,				Six Months Ended March 31,
(in millions)	2026		2025		2026		2025
Dividend income on long equity positions	$	34.8	$	37.3	$	70.9	$	72.9
Dividend expense on short equity positions	35.5		35.2		71.7		71.6
Dividend (expense)/income, net reported within Principal gains, net	$	(0.7)	$	2.1	$	(0.8)	$	1.3

Remaining Performance Obligations

Remaining performance obligations are services that the Company has committed to perform in the future in connection with its contracts with clients. The Company’s remaining performance obligations are generally related to its risk management consulting and asset management contracts with clients. Revenues associated with remaining performance obligations related to these contracts with clients are not material to the overall consolidated results of the Company. For the Company’s asset management activities, where fees are calculated based on a percentage of the fair value of eligible assets in clients’ accounts, future revenue associated with remaining performance obligations cannot be determined as such fees are subject to fluctuations in the fair value of eligible assets in clients’ accounts.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-9

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-10

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-15

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-13

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org/606/tableOfContent

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