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Allowance for Credit Losses and Credit Quality of Loans, Allowance for Credit Losses on Off-Balance Sheet Credit Exposures (Details) - USD ($) $ in Thousands | 12 Months Ended |
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Allowance for Credit Losses and Credit Quality of Loans [Abstract] |  |  |  |
Allowance for credit losses | $ 116,000 | $ 114,400 | $ 100,800 | $ 92,000
Unfunded Loan Commitments [Member] |  |  |  |
Allowance for Credit Losses and Credit Quality of Loans [Abstract] |  |  |  |
Allowance for credit losses | 4,400 | 5,100 |  |
Reserve for credit losses | $ (700) | 100 | $ 100 |
Salisbury acquisition-related provision for credit losses |  | $ 800 |  |

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