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

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Baseline probability weighted scenario to calculate expected credit losses.

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Downside probability weighted scenario to calculate expected credit losses.

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Amount of loans purchased with credit deterioration during the period.

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

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Indicates line item in statement of financial position that includes accrued interest, after allowance for credit loss, on financing receivable.

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

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

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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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Allowance for Credit Losses and Credit Quality of Loans, Summary (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2024	Dec. 31, 2023	Jun. 30, 2024	Sep. 30, 2023	Aug. 11, 2023	Jun. 30, 2023	Dec. 31, 2022
Allowance for Credit Losses [Abstract]
Allowance for credit losses	$ 119,500	$ 114,400	$ 120,500	$ 114,601		$ 100,400
Percentage of allowance of credit losses	1.21%	1.19%
Forecast scenario weighting, baseline	80.00%	70.00%	80.00%
Forecast scenario weighting, downside	20.00%	30.00%	20.00%
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				114,601			$ 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	$ 34,200	$ 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	$ 26,646	$ 22,070	$ 25,874	20,607		$ 15,554
Amount of loans purchased	$ 2,000	$ 3,800
Premium on loans purchased	7.00%	7.00%
Allowance for credit losses on loans purchased	$ 20	$ 31
Residential [Member] \| ASU 2022-02 [Member]
Allowance for Credit Losses [Abstract]
Allowance for credit losses				$ 20,607			$ 14,539