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Acquisitions, Accounting for Acquired Loans (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
May 02, 2025 | Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Merger and Acquisition [Abstract] |  |  |  |  |
Merger and acquisition integration related expenses |  | $ 1,125 | $ 543 | $ 19,526 | $ 543
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 |  | $ 1,100 |  | $ 19,500 |

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- Definition Amount of discount (premium) attributable to other factors on financing receivable purchased with credit deterioration. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 19 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-19 + Details
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