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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 | 3 Months Ended | 9 Months Ended |
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Sep. 30, 2024 | Jun. 30, 2024 | Sep. 30, 2023 | Jun. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | Dec. 31, 2023
Allowance for Credit Losses and Credit Quality of Loans [Abstract] |  |  |  |  |  |  |
Allowance for credit losses | $ 119,500 | $ 120,500 | $ 114,601 | $ 100,400 | $ 119,500 | $ 114,601 | $ 114,400
Unfunded Loan Commitments [Member] |  |  |  |  |  |  |
Allowance for Credit Losses and Credit Quality of Loans [Abstract] |  |  |  |  |  |  |
Allowance for credit losses | 4,600 |  |  |  | 4,600 |  | $ 5,100
Reserve for credit losses | $ 300 | $ (400) |  | $ 500 | $ (600) | $ (300) |
Salisbury acquisition-related provision for credit losses |  |  | $ 800 |  |  |  |

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