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Derivatives (Narrative) (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2023 USD ($) contracts | Dec. 31, 2022 USD ($) contracts | Dec. 31, 2021 USD ($)
Derivative Instruments and Hedging Activities Disclosure [Abstract] |  |  |
Counterparty default losses on forward contracts | $ 0 | $ 0 | $ 0
Collateralized Financings | 815 | 3,800 |
Credit Derivatives [Line Items] |  |  |
Commitments and contingent liabilities |  |  |
Termination value of derivatives in net liability position | 260,100 | 270,000 |
Required collateral posting | 88,300 | 89,500 |
Variation Margin Payment | $ 166,300 | $ 209,500 |
Customer swaps offset by a swap executed on a bilateral basis with a counterparty bank | 252 | 71 |
Counterparty bank cash as collateral on bilateral positions | $ 61,600 | $ 51,900 |
Interest Rate Futures Contracts |  |  |
Credit Derivatives [Line Items] |  |  |
Notional amount of credit risk derivatives | 150,000 | 152,000 |
Mortgage-Backed Security |  |  |
Credit Derivatives [Line Items] |  |  |
Notional amount of credit risk derivatives | 36,000 | 10,000 |
Interest rate swaps |  |  |
Credit Derivatives [Line Items] |  |  |
Notional amount of credit risk derivatives | $ 9,100,000 | $ 7,300,000 |
Number of interest rate derivatives held | contracts | 1,292 | 922 |
Commitments To Originate Loans Held For Sale |  |  |
Credit Derivatives [Line Items] |  |  |
Commitments and contingent liabilities | $ 20,588 | $ 56,100 |
Forward Sales Commitments |  |  |
Credit Derivatives [Line Items] |  |  |
Commitments and contingent liabilities | $ 39,500 | $ 104,000 |

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