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Derivative liabilities related to sale of a portion of Visa class B shares.

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Hedged Amount of Foreign Currency Denominated Loans

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Held-to-maturity trust preferred loans.

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The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

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No definition available.

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- Definition

Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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Fair value, after offset of derivative liability, of 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, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, after offset of derivative asset, of 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, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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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.

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Nominal or face amount used to calculate payment on derivative.

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Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Maximum period the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Amount of gain (loss) resulting from the difference between the acquisition price and the selling price or fair value of trading assets and trading liabilities, conducted separately from customer trading activities. Includes, but is not limited to, changes in fair value of trading assets and trading liabilities.

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Derivatives - Narrative (Details) - USD ($) $ in Millions		3 Months Ended				9 Months Ended
Derivatives - Narrative (Details) - USD ($) $ in Millions	Nov. 01, 2019	Sep. 30, 2019	Sep. 30, 2018	Mar. 31, 2017	Mar. 31, 2016	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Total trading revenues		$ 63.6	$ 34.3			$ 162.7	$ 102.3
Cash flow hedge length of time					5 years
Hedged amount of foreign currency denominated loans		21.3				21.3		$ 11.0
Cash Flow Hedge \| Hedged Items
Derivative Instruments, Gain (Loss) [Line Items]
Variability in cash flows related to debt instruments (primarily loans)					$ 250.0
Notional				$ 650.0
Visa Class B Shares
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liabilities related to sale		28.1				28.1		31.5
Additional Derivative Agreements \| Derivative Instruments With Adjustable Collateral Posting Thresholds
Derivative Instruments, Gain (Loss) [Line Items]
Net fair value of derivative assets with adjustable posting thresholds		92.3				92.3		15.0
Net fair value of derivative liabilities with adjustable posting thresholds		3.3				3.3		34.9
Collateral received		165.4				165.4		80.2
Securities posted collateral		21.6				21.6		13.3
Additional Derivative Agreements \| Derivative Instruments With Accelerated Termination Provisions
Derivative Instruments, Gain (Loss) [Line Items]
Net fair value of derivative assets with adjustable posting thresholds		92.3				92.3		19.0
Net fair value of derivative liabilities with adjustable posting thresholds		7.2				7.2		33.2
Collateral received		165.4				165.4		84.5
Securities posted collateral		26.1				26.1		15.2
Minimum \| Cash Flow Hedge \| Hedged Items
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, term of contract				3 years
Maximum \| Cash Flow Hedge \| Hedged Items
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, term of contract				7 years
Counterparties
Derivative Instruments, Gain (Loss) [Line Items]
Collateral cash receivables		127.3				127.3		76.0
Collateral cash payables		55.7				55.7		$ 34.0
Senior Subordinated Notes [Member] \| Senior Debt Maturing In December 2019
Derivative Instruments, Gain (Loss) [Line Items]
Term borrowings		400.0				400.0
Senior Subordinated Notes [Member] \| Senior Debt Maturing In December 2019 \| Subsequent Event
Derivative Instruments, Gain (Loss) [Line Items]
Debt redeemed	$ 400.0
Senior Subordinated Notes [Member] \| Senior Debt Maturing In December 2020
Derivative Instruments, Gain (Loss) [Line Items]
Term borrowings		$ 500.0				$ 500.0