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Derivatives (Narrative) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023 | Dec. 31, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract] |  |  |  |  |
Counterparty default losses on forward contracts | $ 0 | $ 0 | $ 0 | $ 0 |
Credit Derivatives [Line Items] |  |  |  |  |
Commitments |  |  |  |  |
Collateral required to be posted under agreements | 89,100 |  | 89,100 |  | 88,300
Variation Margin Adjustment | 197,400 |  | 197,400 |  | 166,300
Interest rate futures |  |  |  |  |
Credit Derivatives [Line Items] |  |  |  |  |
Derivative, notional amount | 159,000 |  | 159,000 |  | 150,000
Mortgage-Backed Security |  |  |  |  |
Credit Derivatives [Line Items] |  |  |  |  |
Derivative, notional amount | 23,000 |  | 23,000 |  | 36,000
Interest rate swaps |  |  |  |  |
Credit Derivatives [Line Items] |  |  |  |  |
Derivative, notional amount |  |  |  |  | 4,700,000
Derivative Asset, Notional Amount | 4,500,000 |  | 4,500,000 |  |
Commitments To Originate Loans Held For Sale |  |  |  |  |
Credit Derivatives [Line Items] |  |  |  |  |
Commitments | 54,322 |  | 54,322 |  | 20,600
Interest rate forward sales commitments |  |  |  |  |
Credit Derivatives [Line Items] |  |  |  |  |
Commitments | $ 82,618 |  | $ 82,618 |  | $ 39,500

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