Collateral posting requirements for clearing members and clearing houses

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Counterparty Default Loss On Forward Contract

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Derivative Credit Risk Valuation Adjustment, Change In Derivative Assets

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Termination value of derivatives in net liability position.

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Variation Margin Adjustment

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Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur.

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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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Number of interest rate derivative instruments held by the entity at the reporting date.

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Derivatives (Narrative) (Details) $ in Thousands	3 Months Ended		9 Months Ended
Derivatives (Narrative) (Details) $ in Thousands	Sep. 30, 2021 USD ($) contracts	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) contracts	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) contracts
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Counterparty default losses on forward contracts	$ 0	$ 0	$ 0	$ 0
Credit Derivatives [Line Items]
Commitments
Termination value of derivatives in a net liability position	8,900		8,900		370
Collateral required to be posted under agreements	89,000		89,000		92,600
Variation Margin Adjustment	(198,700)		(198,700)		(330,500)
Decrease in settlement values of net derivative assets	$ (9,700)		$ (9,700)		$ (18,500)
Interest rate swaps
Credit Derivatives [Line Items]
Number of interest rate swaps \| contracts	914		914		886
Derivative, Notional Amount	$ 6,600,000		$ 6,600,000		$ 6,200,000
Commitments To Originate Loans Held For Sale
Credit Derivatives [Line Items]
Commitments	432,659		432,659
Interest rate forward sales commitments
Credit Derivatives [Line Items]
Commitments	$ 555,170		$ 555,170