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Loans Receivable, Allowance for Credit Losses and Credit Quality - Loans modified to borrowers experiencing financial difficulty (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Loans Receivable, Allowance for Credit Losses and Credit Quality
Percentage of loans modified	100.00%	100.00%		100.00%
Net Charge off	$ 693	$ 844	$ 5,305	$ 3,441	$ 8,191
Interest rate reduction
Loans Receivable, Allowance for Credit Losses and Credit Quality
Loans modified in period	$ 37,098			$ 37,098
Term extension and interest rate increase
Loans Receivable, Allowance for Credit Losses and Credit Quality
Loans modified in period			6,200		6,200
Commercial
Loans Receivable, Allowance for Credit Losses and Credit Quality
Percentage of loans modified	67.48%	65.44%		67.48%
Commercial | Commercial real estate | Interest rate reduction
Loans Receivable, Allowance for Credit Losses and Credit Quality
Loans modified in period	$ 37,098			$ 37,098
Percentage of loans modified	2.00%			2.00%
Commercial | Commercial real estate | Term extension and interest rate increase
Loans Receivable, Allowance for Credit Losses and Credit Quality
Loans modified in period			$ 6,200		$ 6,200
Percentage of loans modified			0.40%		0.40%
Net Charge off			$ 3,100		$ 3,100

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- Definition

Percentage, before allowance for credit loss, of financing receivable to total financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
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-Paragraph c
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-Topic 310
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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
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Amortized cost of financing receivable modified during period for debtor experiencing financial difficulty.

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