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Assets and Liabilities, at Fair Value - Financial Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Millions | Sep. 30, 2022 | Sep. 30, 2021
--- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and cash equivalents | $ 805.7 | $ 14.1
Securities and other assets segregated under federal and other regulations | 3,267.2 | 2,274.4
Financial instruments owned | 4,167.3 | 4,354.6
Physical commodities inventory | 513.5 | 447.5
Accounts payable and other accrued liabilities | 400.6 | 305.1
Payable to broker-dealers, clearing organizations and counterparties | 659.8 | 613.5
Financial instruments sold, not yet purchased, at fair value | 2,469.6 | 1,771.2
Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and cash equivalents | 43.5 | 20.8
Securities and other assets segregated under federal and other regulations | 805.7 | 14.1
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net | 2,817.2 | 1,070.6
Receivables from clients, net - Derivatives | (0.5) | 2.6
Financial instruments owned | 4,167.3 | 4,354.6
Total assets at fair value | 8,193.0 | 5,822.6
Payables to clients - Derivatives | (1,392.4) | 291.5
Total liabilities at fair value | 1,133.0 | 2,078.2
Fair Value, Measurements, Recurring | TBA 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 | 58.0 | 12.7
Fair Value, Measurements, Recurring | Derivatives |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Payable to broker-dealers, clearing organizations and counterparties | (2.2) | 0.0
Fair Value, Measurements, Recurring | Payables 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 | 55.8 | 12.7
Fair Value, Measurements, Recurring | Contingent Consideration |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Accounts payable and other accrued liabilities |  | 2.8
Fair Value, Measurements, Recurring | Physical commodities inventory |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Physical commodities inventory | 359.8 | 359.9
Fair Value, Measurements, Recurring | Equity securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 379.7 | 527.0
Financial instruments sold, not yet purchased, at fair value | 305.6 | 436.1
Fair Value, Measurements, Recurring | Corporate and municipal bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 156.8 | 150.8
Financial instruments sold, not yet purchased, at fair value | 63.2 | 51.1
Fair Value, Measurements, Recurring | U.S. Treasury obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 347.6 | 433.1
Financial instruments sold, not yet purchased, at fair value | 1,686.5 | 851.2
Fair Value, Measurements, Recurring | U.S. government agency obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 343.0 | 327.6
Financial instruments sold, not yet purchased, at fair value | 24.3 |
Fair Value, Measurements, Recurring | Foreign government obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 4.8 | 0.0
Financial instruments sold, not yet purchased, at fair value | 0.5 |
Fair Value, Measurements, Recurring | Agency mortgage-backed obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 2,588.7 | 2,599.8
Financial instruments sold, not yet purchased, at fair value | 5.4 | 63.4
Fair Value, Measurements, Recurring | Asset-backed obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 70.7 | 110.4
Fair Value, Measurements, Recurring | Derivatives |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 192.6 | 144.3
Financial instruments sold, not yet purchased, at fair value | 313.4 | 368.5
Fair Value, Measurements, Recurring | Commodities leases |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 26.4 | 18.1
Financial instruments sold, not yet purchased, at fair value |  | 0.9
Fair Value, Measurements, Recurring | Commodities warehouse receipts |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 24.9 | 21.4
Fair Value, Measurements, Recurring | Exchange firm common stock |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 10.6 | 11.6
Fair Value, Measurements, Recurring | Mutual funds and other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 21.5 | 10.5
Fair Value, Measurements, Recurring | Cash flow hedges |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments sold, not yet purchased, at fair value | 70.6 |
Fair Value, Measurements, Recurring | Other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments sold, not yet purchased, at fair value | 0.1 |
Fair Value, Measurements, Recurring | TBA 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 | 116.2 | 19.0
Fair Value, Measurements, Recurring | 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 | 14.4 | 12.2
Fair Value, Measurements, Recurring | 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 | 4,258.5 | 798.5
Fair Value, Measurements, Recurring | 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 | (1,571.9) | 240.9
Fair Value, Measurements, Recurring | 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 | 19.7 | 13.9
Fair Value, Measurements, Recurring | 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 | 786.0 | 0.2
Fair Value, Measurements, Recurring | Certificates of deposit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets | 4.0 | 7.9
Fair Value, Measurements, Recurring | Money market mutual funds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets | 39.5 | 12.9
Fair Value, Measurements, Recurring | 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 | (9,839.1) | (4,442.4)
Receivables from clients, net - Derivatives | (579.3) | (411.1)
Financial instruments owned | (502.4) | (500.4)
Total assets at fair value | (10,920.8) | (5,353.9)
Payables to clients - Derivatives | (9,290.3) | (4,278.4)
Financial instruments sold, not yet purchased, at fair value | (466.3) | (335.0)
Total liabilities at fair value | (10,505.0) | (4,955.4)
Fair Value, Measurements, Recurring | Netting | TBA 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 | (96.9) | (39.5)
Fair Value, Measurements, Recurring | Netting | Derivatives |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Payable to broker-dealers, clearing organizations and counterparties | (651.5) | (302.5)
Fair Value, Measurements, Recurring | Netting | Payables 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 | (748.4) | (342.0)
Fair Value, Measurements, Recurring | Netting | Contingent Consideration |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Accounts payable and other accrued liabilities |  | 0.0
Fair Value, Measurements, Recurring | Netting | Physical commodities inventory |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Physical commodities inventory | 0.0 | 0.0
Fair Value, Measurements, Recurring | 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, at fair value | 0.0 | 0.0
Fair Value, Measurements, Recurring | 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, at fair value | 0.0 | 0.0
Fair Value, Measurements, Recurring | 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, at fair value | 0.0 | 0.0
Fair Value, Measurements, Recurring | 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, at fair value | 0.0 |
Fair Value, Measurements, Recurring | Netting | Foreign government 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, at fair value | 0.0 |
Fair Value, Measurements, Recurring | 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, at fair value | 0.0 | 0.0
Fair Value, Measurements, Recurring | Netting | Asset-backed obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 0.0 | 0.0
Fair Value, Measurements, Recurring | Netting | Derivatives |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | (502.4) | (500.4)
Financial instruments sold, not yet purchased, at fair value | (466.3) | (335.0)
Fair Value, Measurements, Recurring | Netting | Commodities leases |  |
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, at fair value |  | 0.0
Fair Value, Measurements, Recurring | Netting | Commodities warehouse receipts |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 0.0 | 0.0
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | Netting | Cash flow hedges |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments sold, not yet purchased, at fair value | 0.0 |
Fair Value, Measurements, Recurring | Netting | Other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments sold, not yet purchased, at fair value | 0.0 |
Fair Value, Measurements, Recurring | Netting | TBA 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 | (91.4) | (40.1)
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | 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 | (9,747.7) | (4,402.3)
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | Netting | Certificates of deposit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets | 0.0 | 0.0
Fair Value, Measurements, Recurring | Netting | Money market mutual funds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets | 0.0 | 0.0
Fair Value, Measurements, Recurring | Level 1 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and cash equivalents | 43.5 | 20.8
Securities and other assets segregated under federal and other regulations | 805.7 | 14.1
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net | 11,987.3 | 5,286.5
Receivables from clients, net - Derivatives | 67.2 | 0.0
Financial instruments owned | 773.9 | 989.6
Total assets at fair value | 13,813.9 | 6,422.2
Payables to clients - Derivatives | 7,722.5 | 4,413.8
Financial instruments sold, not yet purchased, at fair value | 1,986.9 | 1,284.3
Total liabilities at fair value | 9,768.1 | 5,761.2
Fair Value, Measurements, Recurring | Level 1 | TBA 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
Fair Value, Measurements, Recurring | Level 1 | Derivatives |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Payable to broker-dealers, clearing organizations and counterparties | 58.7 | 63.1
Fair Value, Measurements, Recurring | Level 1 | Payables 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 | 58.7 | 63.1
Fair Value, Measurements, Recurring | Level 1 | Contingent Consideration |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Accounts payable and other accrued liabilities |  | 0.0
Fair Value, Measurements, Recurring | Level 1 | Physical commodities inventory |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Physical commodities inventory | 136.3 | 111.2
Fair Value, Measurements, Recurring | Level 1 | Equity securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 367.9 | 512.4
Financial instruments sold, not yet purchased, at fair value | 299.9 | 429.9
Fair Value, Measurements, Recurring | 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, at fair value | 0.0 | 0.0
Fair Value, Measurements, Recurring | Level 1 | U.S. Treasury obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 347.6 | 433.1
Financial instruments sold, not yet purchased, at fair value | 1,686.5 | 851.2
Fair Value, Measurements, Recurring | 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, at fair value | 0.0 |
Fair Value, Measurements, Recurring | Level 1 | Foreign government obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 4.8 | 0.0
Financial instruments sold, not yet purchased, at fair value | 0.5 |
Fair Value, Measurements, Recurring | 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, at fair value | 0.0 | 0.0
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | Level 1 | Derivatives |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 0.7 | 0.6
Financial instruments sold, not yet purchased, at fair value | 0.0 | 3.2
Fair Value, Measurements, Recurring | Level 1 | Commodities leases |  |
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, at fair value |  | 0.0
Fair Value, Measurements, Recurring | Level 1 | Commodities warehouse receipts |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 24.9 | 21.4
Fair Value, Measurements, Recurring | Level 1 | Exchange firm common stock |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 10.6 | 11.6
Fair Value, Measurements, Recurring | Level 1 | Mutual funds and other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 17.4 | 10.5
Fair Value, Measurements, Recurring | Level 1 | Cash flow hedges |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments sold, not yet purchased, at fair value | 0.0 |
Fair Value, Measurements, Recurring | Level 1 | Other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments sold, not yet purchased, at fair value | 0.0 |
Fair Value, Measurements, Recurring | Level 1 | TBA 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
Fair Value, Measurements, Recurring | 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 | 14.4 | 12.2
Fair Value, Measurements, Recurring | 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 | 4,258.5 | 798.5
Fair Value, Measurements, Recurring | 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 | 7,714.4 | 4,475.8
Fair Value, Measurements, Recurring | 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 | 19.7 | 13.9
Fair Value, Measurements, Recurring | 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 | 786.0 | 0.2
Fair Value, Measurements, Recurring | Level 1 | Certificates of deposit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets | 4.0 | 7.9
Fair Value, Measurements, Recurring | Level 1 | Money market mutual funds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets | 39.5 | 12.9
Fair Value, Measurements, Recurring | 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 | 0.0 | 0.0
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net | 669.0 | 226.5
Receivables from clients, net - Derivatives | 511.6 | 413.7
Financial instruments owned | 3,895.8 | 3,865.4
Total assets at fair value | 5,299.9 | 4,754.3
Payables to clients - Derivatives | 175.4 | 156.1
Financial instruments sold, not yet purchased, at fair value | 949.0 | 821.9
Total liabilities at fair value | 1,869.9 | 1,269.6
Fair Value, Measurements, Recurring | Level 2 | TBA 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 | 154.9 | 52.2
Fair Value, Measurements, Recurring | Level 2 | Derivatives |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Payable to broker-dealers, clearing organizations and counterparties | 590.6 | 239.4
Fair Value, Measurements, Recurring | Level 2 | Payables 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 | 745.5 | 291.6
Fair Value, Measurements, Recurring | Level 2 | Contingent Consideration |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Accounts payable and other accrued liabilities |  | 0.0
Fair Value, Measurements, Recurring | Level 2 | Physical commodities inventory |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Physical commodities inventory | 223.5 | 248.7
Fair Value, Measurements, Recurring | Level 2 | Equity securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 11.8 | 14.6
Financial instruments sold, not yet purchased, at fair value | 5.7 | 6.2
Fair Value, Measurements, Recurring | Level 2 | Corporate and municipal bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 156.8 | 150.8
Financial instruments sold, not yet purchased, at fair value | 63.2 | 51.1
Fair Value, Measurements, Recurring | 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, at fair value | 0.0 | 0.0
Fair Value, Measurements, Recurring | Level 2 | U.S. government agency obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 343.0 | 327.6
Financial instruments sold, not yet purchased, at fair value | 24.3 |
Fair Value, Measurements, Recurring | Level 2 | Foreign government 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, at fair value | 0.0 |
Fair Value, Measurements, Recurring | Level 2 | Agency mortgage-backed obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 2,588.7 | 2,599.8
Financial instruments sold, not yet purchased, at fair value | 5.4 | 63.4
Fair Value, Measurements, Recurring | Level 2 | Asset-backed obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 70.7 | 110.4
Fair Value, Measurements, Recurring | Level 2 | Derivatives |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 694.3 | 644.1
Financial instruments sold, not yet purchased, at fair value | 779.7 | 700.3
Fair Value, Measurements, Recurring | Level 2 | Commodities leases |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 26.4 | 18.1
Financial instruments sold, not yet purchased, at fair value |  | 0.9
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | Level 2 | Mutual funds and other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 4.1 | 0.0
Fair Value, Measurements, Recurring | Level 2 | Cash flow hedges |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments sold, not yet purchased, at fair value | 70.6 |
Fair Value, Measurements, Recurring | Level 2 | Other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments sold, not yet purchased, at fair value | 0.1 |
Fair Value, Measurements, Recurring | Level 2 | TBA 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 | 207.6 | 59.1
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | 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 | 461.4 | 167.4
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | Level 2 | Certificates of deposit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets | 0.0 | 0.0
Fair Value, Measurements, Recurring | Level 2 | Money market mutual funds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets | 0.0 | 0.0
Fair Value, Measurements, Recurring | 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 |  |
Financial instruments owned | 0.0 | 0.0
Total assets at fair value | 0.0 | 0.0
Payables to clients - Derivatives | 0.0 | 0.0
Financial instruments sold, not yet purchased, at fair value | 0.0 | 0.0
Total liabilities at fair value | 0.0 | 2.8
Fair Value, Measurements, Recurring | Level 3 | TBA 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
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | Level 3 | Payables 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
Fair Value, Measurements, Recurring | Level 3 | Contingent Consideration |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Accounts payable and other accrued liabilities | 0.0 | 2.8
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | 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, at fair value | 0.0 | 0.0
Fair Value, Measurements, Recurring | 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, at fair value | 0.0 | 0.0
Fair Value, Measurements, Recurring | 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, at fair value | 0.0 | 0.0
Fair Value, Measurements, Recurring | 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, at fair value | 0.0 |
Fair Value, Measurements, Recurring | 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
Financial instruments sold, not yet purchased, at fair value | 0.0 |
Fair Value, Measurements, Recurring | 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, at fair value | 0.0 | 0.0
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | 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, at fair value | 0.0 | 0.0
Fair Value, Measurements, Recurring | Level 3 | Commodities leases |  |
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, at fair value |  | 0.0
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | Level 3 | Mutual funds and other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments owned | 0.0 | 0.0
Fair Value, Measurements, Recurring | Level 3 | Cash flow hedges |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments sold, not yet purchased, at fair value | 0.0 |
Fair Value, Measurements, Recurring | Level 3 | Other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial instruments sold, not yet purchased, at fair value | 0.0 |
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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
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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
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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
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | 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
Fair Value, Measurements, Recurring | Level 3 | Certificates of deposit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets | 0.0 | 0.0
Fair Value, Measurements, Recurring | Level 3 | Money market mutual funds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets | $ 0.0 | $ 0.0

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