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Allowance for Credit Losses and Credit Quality of Loans, Summary (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Allowance for Credit Losses [Abstract]
Allowance for credit losses	$ 116,000	$ 114,400	$ 100,800	$ 92,000
Percentage of allowance of credit losses	1.16%	1.19%
Forecast scenario weighting, baseline	80.00%	70.00%
Forecast scenario weighting, downside	20.00%	30.00%
Salisbury Bank [Member]
Allowance for Credit Losses [Abstract]
Loans purchased with credit deterioration	$ 0	$ 219,500
Allowance for credit losses on loans purchased		5,800
Allowance for credit losses at acquisition		14,500
Salisbury Bank [Member] | PCD [Member]
Allowance for Credit Losses [Abstract]
Allowance for credit losses at acquisition		5,800
Salisbury Bank [Member] | Non-PCD [Member]
Allowance for Credit Losses [Abstract]
Allowance for credit losses at acquisition		8,800
ASU 2022-02 [Member]
Allowance for Credit Losses [Abstract]
Allowance for credit losses		114,400	100,152
Loans [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | ASU 2022-02 [Member]
Allowance for Credit Losses [Abstract]
Allowance for credit losses			(600)
Accrued Interest Receivable [Member]
Allowance for Credit Losses [Abstract]
Allowance for credit losses	0	0
AIR on loans	$ 34,800	$ 34,100
Financing Receivable, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Other Assets	Other Assets
Residential [Member]
Allowance for Credit Losses [Abstract]
Allowance for credit losses	$ 26,560	$ 22,070	15,127	18,806
Amount of loans purchased	$ 3,000	$ 3,800
Premium on loans purchased	7.00%	7.00%
Allowance for credit losses on loans purchased	$ 31	$ 31
Residential [Member] | ASU 2022-02 [Member]
Allowance for Credit Losses [Abstract]
Allowance for credit losses		22,070	14,539
Consumer Loans [Member]
Allowance for Credit Losses [Abstract]
Allowance for credit losses	$ 43,987	46,427	50,951	$ 44,253
Consumer Loans [Member] | ASU 2022-02 [Member]
Allowance for Credit Losses [Abstract]
Allowance for credit losses		$ 46,427	$ 50,951

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- Definition

Amount of allowance for credit loss at acquisition date of financing receivable purchased.

+ References

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- Definition

Baseline probability weighted scenario to calculate expected credit losses.

+ References

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- Definition

Downside probability weighted scenario to calculate expected credit losses.

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- Definition

Amount of loans purchased with credit deterioration during the period.

+ References

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- Definition

The premium percentage on loans purchased.

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- Definition

Percentage of allowance for credit loss to total financing receivable outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
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-Publisher SEC

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- Definition

Amount, after allowance for credit loss, of accrued interest on financing receivable.

+ References

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- Definition

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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- Definition

Amount, excluding accrued interest, of allowance for credit loss at acquisition date of financing receivable purchased with credit deterioration. Excludes net investment in lease.

+ References

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The cash outflow for the purchase of loan receivable arising from the financing of goods and services.

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