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Acquisitions, Accounting for Acquired Loans (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Aug. 11, 2023 | Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Merger and Acquisition [Abstract] |  |  |  |  |
Merger and acquisition integration related expenses |  | $ 7,917 | $ 0 | $ 9,724 | $ 0
Salisbury Bancorp, Inc [Member] |  |  |  |  |
Accounting for Acquired Loans [Abstract] |  |  |  |  |
Allowance for credit losses on non-PCD loans | $ 8,800 |  |  |  |
Par value of PCD loans at acquisition | 219,076 |  |  |  |
Allowance for credit losses at acquisition | 5,772 |  |  |  |
Discount at acquisition | (24,512) |  |  |  |
Fair value of PCD loans at acquisition | $ 200,336 |  |  |  |
Merger and Acquisition [Abstract] |  |  |  |  |
Merger and acquisition integration related expenses |  | $ 7,900 |  | $ 9,700 |

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- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479405/805-10-25-23 + Details
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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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