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Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2024 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 18, 2023
Stockholders' Equity [Abstract] |  |  |  |  |
Unrecognized prior service cost and net actuarial (losses) on pension plans | $ (18,103) | $ (18,103) | $ (21,983) | $ (26,435) |
Unrealized net holding (losses) on AFS securities | (123,995) | (123,995) | (138,951) | (163,599) |
AOCI | (142,098) | $ (142,098) | $ (160,934) | $ (190,034) |
Preceding period of retained net profits for approval of Office of Comptroller of the Currency |  | 2 years |  |  |
Statutory amount available for dividend payments | $ 107,600 | $ 107,600 |  |  |
Stock Repurchase Program [Abstract] |  |  |  |  |
Purchase of common stock (in shares) | 0 | 7,600 | 155,500 | 400,000 |
Purchase of common stock value |  | $ 251 | $ 4,944 | $ 14,713 |
Average price per share (in dollars per share) |  | $ 33.02 |  |  |
Number of shares authorized under stock repurchase program (in shares) |  |  |  |  | 2,000,000
Number of shares available for repurchase under stock repurchase program (in shares) | 1,992,400 | 1,992,400 |  |  |

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