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Acquisitions, Accounting for Acquired Loans (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | ---
May 02, 2025 | Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Merger and Acquisition [Abstract] |  |  |  |  |
Merger and acquisition integration related expenses |  | $ 17,180 | $ 0 | $ 18,401 | $ 0
Evans Bancorp, Inc [Member] |  |  |  |  |
Accounting for Acquired Loans [Abstract] |  |  |  |  |
Allowance for credit losses on non-PCD loans | $ 13,000 |  |  |  |
Par value of PCD loans at acquisition | 336,398 |  |  |  |
Allowance for credit losses at acquisition | 7,726 |  |  |  |
Discount at acquisition | (36,584) |  |  |  |
Fair value of PCD loans at acquisition | $ 307,540 |  |  |  |
Merger and Acquisition [Abstract] |  |  |  |  |
Merger and acquisition integration related expenses |  | $ 17,200 |  | $ 18,400 |

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