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Assets and Liabilities, at Fair Value - Financial Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Jun. 30, 2020 | Sep. 30, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Cash Equivalents, Fair Value Disclosure | $ 9.8 | $ 306.0
Cash and Securities Segregated under Federal and Other Regulations | 1,145.2 | 1,049.9
Deposits with and receivables from broker-dealers, clearing organizations and counterparties, net (including $1261.6 and $626.9 at fair value at June 30, 2020 and September 30, 2019, respectively) | 3,396.7 | 2,540.5
Financial Instruments, Owned, at Fair Value | 2,831.9 | 2,175.2
Physical commodities inventory | 270.2 | 229.3
Accounts Payable and Other Accrued Liabilities | 176.4 | 157.5
Broker-Dealer, Payable to Other Broker-Dealer and Clearing Organization | (430.0) | (266.2)
Financial Instruments Sold, Not yet Purchased, at Fair Value | $ 728.3 | 714.8
Document Period End Date | Jun. 30, 2020 |
Fair Value, Recurring [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Securities Segregated under Federal and Other Regulations | $ 9.8 | 306.0
Receivables from Clearing Organizations | 1,261.6 | 626.9
Financial Instruments, Owned, at Fair Value | 2,831.9 | 2,175.2
Assets, Fair Value Disclosure | 4,291.0 | 3,273.8
Financial Instruments Sold, Not yet Purchased, at Fair Value | 728.3 |
Liabilities, Fair Value Disclosure | 738.7 | 722.2
Fair Value, Recurring [Member] | TBA and forward settling securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Broker-Dealer, Payable to Other Broker-Dealer and Clearing Organization | (7.3) | (5.3)
Fair Value, Recurring [Member] | Derivative [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Broker-Dealer, Payable to Other Broker-Dealer and Clearing Organization | (1.5) | (0.3)
Fair Value, Recurring [Member] | Payable to broker-dealers, clearing organizations and counterparties [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Broker-Dealer, Payable to Other Broker-Dealer and Clearing Organization | (8.8) | (5.6)
Fair Value, Recurring [Member] | Contingent Consideration [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Accounts Payable and Other Accrued Liabilities | 1.6 | 1.8
Fair Value, Recurring [Member] | Physical commodities inventory [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Physical commodities inventory | 173.6 | 151.9
Fair Value, Recurring [Member] | Asset-backed Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 19.4 | 29.1
Fair Value, Recurring [Member] | US Government Agencies Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 347.8 | 447.1
Financial Instruments Sold, Not yet Purchased, at Fair Value | 6.1 | 43.8
Fair Value, Recurring [Member] | US Government Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 372.5 | 248.7
Financial Instruments Sold, Not yet Purchased, at Fair Value | 354.1 | 272.3
Fair Value, Recurring [Member] | Debt Security, Government, Non-US [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 12.6 | 0.5
Financial Instruments Sold, Not yet Purchased, at Fair Value | 2.2 |
Fair Value, Recurring [Member] | Derivative [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 92.4 | 66.5
Fair Value, Recurring [Member] | Commodities leases [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 23.2 | 28.6
Financial Instruments Sold, Not yet Purchased, at Fair Value | 2.4 | 113.7
Fair Value, Recurring [Member] | Commodities warehouse receipts [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 56.4 | 48.4
Fair Value, Recurring [Member] | Exchange firm common stock [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 9.8 | 12.7
Fair Value, Recurring [Member] | Mutual funds and other [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 3.4 | 0.1
Fair Value, Recurring [Member] | Equity Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 260.7 | 168.5
Financial Instruments Sold, Not yet Purchased, at Fair Value | 217.6 | 158.1
Fair Value, Recurring [Member] | Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 75.4 | 80.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 26.1 | 39.2
Fair Value, Recurring [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 1,558.3 | 1,045.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 21.1 | 29.6
Fair Value, Recurring [Member] | US Government Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | 1,148.4 |
Fair Value, Recurring [Member] | Debt Security, Government, Non-US [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | 8.2 | 9.9
Fair Value, Recurring [Member] | TBA and forward settling securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | 6.9 | 8.3
Fair Value, Recurring [Member] | Derivative [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Broker-Dealer, Payable to Other Broker-Dealer and Clearing Organization | 98.1 |
Fair Value, Recurring [Member] | Commodities warehouse receipts [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Securities Segregated under Federal and Other Regulations | 9.6 | 6.2
Fair Value, Recurring [Member] | US Government Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Securities Segregated under Federal and Other Regulations | 0.2 | 299.8
Fair Value, Recurring [Member] | Money Market Funds [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Cash Equivalents, Fair Value Disclosure | 11.4 | 8.9
Fair Value, Recurring [Member] | Certificates of Deposit [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Cash Equivalents, Fair Value Disclosure | 2.7 | 4.9
Fair Value, Recurring [Member] | Cash Equivalents [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Cash Equivalents, Fair Value Disclosure | 14.1 | 13.8
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Securities Segregated under Federal and Other Regulations | 0.0 | 0.0
Receivables from Clearing Organizations | (2,797.8) | (3,161.1)
Financial Instruments, Owned, at Fair Value | (880.0) | (420.8)
Assets, Fair Value Disclosure | (3,677.8) | (3,581.9)
Financial Instruments Sold, Not yet Purchased, at Fair Value | (838.3) | (422.2)
Liabilities, Fair Value Disclosure | (3,785.3) | (3,540.8)
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | TBA and forward settling securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Broker-Dealer, Payable to Other Broker-Dealer and Clearing Organization | 5.3 | 1.5
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Derivative [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Broker-Dealer, Payable to Other Broker-Dealer and Clearing Organization | 2,941.7 | 3,117.1
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Payable to broker-dealers, clearing organizations and counterparties [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Broker-Dealer, Payable to Other Broker-Dealer and Clearing Organization | 2,947.0 | 3,118.6
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Contingent Consideration [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Accounts Payable and Other Accrued Liabilities | 0.0 | 0.0
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Physical commodities inventory [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Physical commodities inventory | 0.0 | 0.0
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Asset-backed Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | US Government Agencies Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | US Government Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Debt Security, Government, Non-US [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 |
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Derivative [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | (880.0) | (420.8)
Financial Instruments Sold, Not yet Purchased, at Fair Value | (838.3) | (422.2)
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Commodities leases [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Commodities warehouse receipts [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Exchange firm common stock [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Mutual funds and other [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Equity Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | US Government Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | 0.0 |
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Debt Security, Government, Non-US [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | 0.0 |
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | TBA and forward settling securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | (5.3) |
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Derivative [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | (2,792.5) |
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Commodities warehouse receipts [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Securities Segregated under Federal and Other Regulations | 0.0 | 0.0
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | US Government Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Securities Segregated under Federal and Other Regulations | 0.0 | 0.0
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Money Market Funds [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Cash Equivalents, Fair Value Disclosure | 0.0 | 0.0
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Certificates of Deposit [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Cash Equivalents, Fair Value Disclosure | 0.0 | 0.0
Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] | Cash Equivalents [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Cash Equivalents, Fair Value Disclosure | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Securities Segregated under Federal and Other Regulations | 9.8 | 306.0
Receivables from Clearing Organizations | 4,033.5 | 3,735.0
Financial Instruments, Owned, at Fair Value | 703.9 | 470.9
Assets, Fair Value Disclosure | 4,781.1 | 4,532.8
Financial Instruments Sold, Not yet Purchased, at Fair Value | 558.5 | 419.6
Liabilities, Fair Value Disclosure | 3,332.4 | 3,498.7
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | TBA and forward settling securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Broker-Dealer, Payable to Other Broker-Dealer and Clearing Organization | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Derivative [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Broker-Dealer, Payable to Other Broker-Dealer and Clearing Organization | (2,773.9) | (3,079.1)
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Payable to broker-dealers, clearing organizations and counterparties [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Broker-Dealer, Payable to Other Broker-Dealer and Clearing Organization | (2,773.9) | (3,079.1)
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Contingent Consideration [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Accounts Payable and Other Accrued Liabilities | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Physical commodities inventory [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Physical commodities inventory | 19.8 | 7.1
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Asset-backed Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | US Government Agencies Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | US Government Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 372.5 | 248.7
Financial Instruments Sold, Not yet Purchased, at Fair Value | 354.1 | 272.3
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Debt Security, Government, Non-US [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 12.6 | 0.5
Financial Instruments Sold, Not yet Purchased, at Fair Value | 2.2 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Derivative [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.5 | 1.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Commodities leases [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Commodities warehouse receipts [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 56.4 | 48.4
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Exchange firm common stock [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 9.8 | 12.7
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Mutual funds and other [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 3.4 | 0.1
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Equity Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 248.7 | 159.5
Financial Instruments Sold, Not yet Purchased, at Fair Value | 202.2 | 147.3
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | US Government Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | 1,148.4 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Debt Security, Government, Non-US [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | 8.2 | 9.9
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | TBA and forward settling securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Derivative [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | 2,876.9 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Commodities warehouse receipts [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Securities Segregated under Federal and Other Regulations | 9.6 | 6.2
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | US Government Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Securities Segregated under Federal and Other Regulations | 0.2 | 299.8
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Money Market Funds [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Cash Equivalents, Fair Value Disclosure | 11.4 | 8.9
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Certificates of Deposit [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Cash Equivalents, Fair Value Disclosure | 2.7 | 4.9
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Cash Equivalents [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Cash Equivalents, Fair Value Disclosure | 14.1 | 13.8
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Securities Segregated under Federal and Other Regulations | 0.0 | 0.0
Receivables from Clearing Organizations | 25.9 | 53.0
Financial Instruments, Owned, at Fair Value | 3,008.0 | 2,125.1
Assets, Fair Value Disclosure | 3,187.7 | 2,322.9
Financial Instruments Sold, Not yet Purchased, at Fair Value | 1,008.1 | 717.4
Liabilities, Fair Value Disclosure | 1,190.0 | 762.5
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | TBA and forward settling securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Broker-Dealer, Payable to Other Broker-Dealer and Clearing Organization | (12.6) | (6.8)
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Derivative [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Broker-Dealer, Payable to Other Broker-Dealer and Clearing Organization | (169.3) | (38.3)
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Payable to broker-dealers, clearing organizations and counterparties [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Broker-Dealer, Payable to Other Broker-Dealer and Clearing Organization | (181.9) | (45.1)
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Contingent Consideration [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Accounts Payable and Other Accrued Liabilities | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Physical commodities inventory [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Physical commodities inventory | 153.8 | 144.8
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Asset-backed Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 19.4 | 29.1
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | US Government Agencies Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 347.8 | 447.1
Financial Instruments Sold, Not yet Purchased, at Fair Value | 6.1 | 43.8
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | US Government Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Debt Security, Government, Non-US [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Derivative [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 971.9 | 486.3
Financial Instruments Sold, Not yet Purchased, at Fair Value | 937.0 | 480.3
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Commodities leases [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 23.2 | 28.6
Financial Instruments Sold, Not yet Purchased, at Fair Value | 2.4 | 113.7
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Commodities warehouse receipts [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Exchange firm common stock [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Mutual funds and other [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Equity Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 12.0 | 9.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 15.4 | 10.8
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 75.4 | 80.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 26.1 | 39.2
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 1,558.3 | 1,045.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 21.1 | 29.6
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | US Government Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | 0.0 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Debt Security, Government, Non-US [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | TBA and forward settling securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | 12.2 | 9.8
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Derivative [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | 13.7 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Commodities warehouse receipts [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Securities Segregated under Federal and Other Regulations | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | US Government Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Securities Segregated under Federal and Other Regulations | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Money Market Funds [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Cash Equivalents, Fair Value Disclosure | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Certificates of Deposit [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Cash Equivalents, Fair Value Disclosure | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Cash Equivalents [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Cash Equivalents, Fair Value Disclosure | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Securities Segregated under Federal and Other Regulations | 0.0 | 0.0
Receivables from Clearing Organizations | 0.0 | 0.0
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Assets, Fair Value Disclosure | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Liabilities, Fair Value Disclosure | 1.6 | 1.8
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | TBA and forward settling securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Broker-Dealer, Payable to Other Broker-Dealer and Clearing Organization | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Broker-Dealer, Payable to Other Broker-Dealer and Clearing Organization | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Payable to broker-dealers, clearing organizations and counterparties [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Broker-Dealer, Payable to Other Broker-Dealer and Clearing Organization | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Contingent Consideration [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Accounts Payable and Other Accrued Liabilities | 1.6 | 1.8
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Physical commodities inventory [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Physical commodities inventory | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Asset-backed Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | US Government Agencies Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | US Government Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Debt Security, Government, Non-US [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Commodities leases [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Commodities warehouse receipts [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Exchange firm common stock [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Mutual funds and other [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Equity Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial Instruments, Owned, at Fair Value | 0.0 | 0.0
Financial Instruments Sold, Not yet Purchased, at Fair Value | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | US Government Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | 0.0 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Debt Security, Government, Non-US [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | TBA and forward settling securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations | 0.0 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Commodities warehouse receipts [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Securities Segregated under Federal and Other Regulations | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | US Government Debt Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Securities Segregated under Federal and Other Regulations | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Money Market Funds [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Cash Equivalents, Fair Value Disclosure | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Certificates of Deposit [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Cash Equivalents, Fair Value Disclosure | 0.0 | 0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Cash Equivalents [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash and Cash Equivalents, Fair Value Disclosure | $ 0.0 | 0.0
TBA and forward settling securities [Member] | Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations |  | (1.5)
Debt Security, Government, Non-US [Member] | Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations |  | 0.0
Derivative [Member] | Fair Value, Recurring [Member] |  |
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 (including $1261.6 and $626.9 at fair value at June 30, 2020 and September 30, 2019, respectively) |  | 14.8
Derivative [Member] | Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations |  | (3,159.6)
Derivative [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations |  | 3,131.2
Derivative [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations |  | 43.2
Derivative [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations |  | 0.0
US Government Debt Securities [Member] | Fair Value, Recurring [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations |  | 593.9
US Government Debt Securities [Member] | Fair Value, Recurring [Member] | Counterparty And Cash Collateral Netting Adjustment [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations |  | 0.0
US Government Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations |  | 593.9
US Government Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations |  | 0.0
US Government Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Receivables from Clearing Organizations |  | $ 0.0

X
- Definition The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD. + References No definition available. + Details
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- Definition Amount payable to other broker-dealer and clearing organization, including, but not limited to, security failed-to-receive, deposit received for security loaned, open transaction, and floor-brokerage payable. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher SEC -Name Rule 15c3-1 -Number 240 -Section 15c3-1 + Details
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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References No definition available. + Details
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- Definition Amount of cash subject to withdrawal restrictions, restricted deposits held as compensating balances, and cash and securities segregated in compliance with regulations (such as cash deposited in a special reserve account for the exclusive benefit of customers). + References No definition available. + Details
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- 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 No definition available. + Details
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- Definition The aggregate fair value as of the balance sheet date of financial instruments and other positions owned by the entity including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. Includes both pledged and unpledged holdings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 320 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=35711157&loc=d3e42546-110969 + Details
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- Definition Fair value of obligations incurred from short sales. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 320 -Section 35 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35711043&loc=d3e42429-110968 + Details
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- Definition Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Fair value of financial and nonfinancial obligations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition Amount receivable from broker-dealers and clearing organizations, including, but not limited to, securities failed-to-deliver, certain deposits for securities borrowed, open transactions, good faith and margin deposits, commissions and floor brokerage receivables. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 20 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=35710130&loc=d3e41645-110958 + Details
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- Definition Amount of right to receive cash and securities on deposit with clearing organizations. Clearing organizations perform post trade processing and trade comparisons among numerous broker-dealers and act as settlement agents between buying and selling broker-dealers. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 310 -URI http://asc.fasb.org/subtopic&trid=2176284 + Details
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