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Derivatives (Narrative) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Dec. 31, 2024
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 | 87,900 |  | 87,900 |  | 87,200
Variation Margin Adjustment | 114,200 |  | 114,200 |  | 173,900
Interest rate futures |  |  |  |  |
Credit Derivatives [Line Items] |  |  |  |  |
Derivative, notional amount | 188,000 |  | 188,000 |  | 187,000
Mortgage-Backed Security |  |  |  |  |
Credit Derivatives [Line Items] |  |  |  |  |
Derivative, notional amount | 17,000 |  | 17,000 |  | 12,000
Interest rate swaps |  |  |  |  |
Credit Derivatives [Line Items] |  |  |  |  |
Derivative Asset, Notional Amount | 4,400,000 |  | 4,400,000 |  | 4,300,000
Derivative Liability, Notional Amount | 4,400,000 |  | 4,400,000 |  | 4,400,000
Commitments To Originate Loans Held For Sale |  |  |  |  |
Credit Derivatives [Line Items] |  |  |  |  |
Commitments | 58,919 |  | 58,919 |  | 46,208
Interest rate forward sales commitments |  |  |  |  |
Credit Derivatives [Line Items] |  |  |  |  |
Commitments | $ 71,500 |  | $ 71,500 |  | $ 76,535

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