Loans, Allowance for Credit Losses and Credit Quality - Amortized Cost of Loan Modifications (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis	$ 32,206	$ 12,507
Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis	23,744	2,645
Other-Than-Insignificant Payment Delay
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis	8,160	9,818
Combination - Interest Rate Reduction and Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis	251	44
Combination - Interest Rate Reduction and Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modified, Accumulated	51	0
Commercial Real Estate [Member] \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis	$ 3,375	$ 2,540
% of Total Class of Financing Receivable	0.04%	0.03%
Added weighted-average contractual term to the life of the loan	6 months	2 months
Commercial Real Estate [Member] \| Other-Than-Insignificant Payment Delay
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis	$ 6,351	$ 7,013
% of Total Class of Financing Receivable	0.08%	0.09%
Small Business [Member] \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis	$ 0	$ 105
% of Total Class of Financing Receivable	0.00%	0.05%
Added weighted-average contractual term to the life of the loan		4 years 3 months 18 days
Small Business [Member] \| Combination - Interest Rate Reduction and Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis	$ 0	$ 44
% of Total Class of Financing Receivable	0.00%	0.02%
Small Business [Member] \| Combination - Interest Rate Reduction and Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
% of Total Class of Financing Receivable	0.02%	0.00%
Financing Receivable, Modified, Accumulated	$ 51	$ 0
Small Business [Member] \| Combination - Interest Rate Reduction and Term Extension \| Maximum [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Reduced weighted-average contractual interest rate	11.00%	10.00%
Small Business [Member] \| Combination - Interest Rate Reduction and Term Extension \| Minimum [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Reduced weighted-average contractual interest rate	8.20%	6.50%
Commercial And Industrial [Member] \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis	$ 9,725	$ 0
% of Total Class of Financing Receivable	0.62%	0.00%
Added weighted-average contractual term to the life of the loan	3 months
Commercial And Industrial [Member] \| Other-Than-Insignificant Payment Delay
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis	$ 1,809	$ 2,805
% of Total Class of Financing Receivable	0.11%	0.17%
Commercial And Industrial [Member] \| Combination - Interest Rate Reduction and Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
% of Total Class of Financing Receivable	0.01%	0.00%
Financing Receivable, Modified, Accumulated	$ 179	$ 0
Added weighted-average contractual term to the life of the loan	1 year 6 months
Commercial And Industrial [Member] \| Combination - Interest Rate Reduction and Term Extension \| Maximum [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Reduced weighted-average contractual interest rate	10.10%
Commercial And Industrial [Member] \| Combination - Interest Rate Reduction and Term Extension \| Minimum [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Reduced weighted-average contractual interest rate	7.20%
Construction Loans [Member] \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis	$ 10,644	$ 0
% of Total Class of Financing Receivable	1.28%	0.00%
Home Equity Loan [Member] \| Combination - Interest Rate Reduction and Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Added weighted-average contractual term to the life of the loan	8 years 1 month 6 days
Home Equity Loan [Member] \| Combination - Interest Rate Reduction and Term Extension \| Maximum [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Reduced weighted-average contractual interest rate	10.00%
Home Equity Loan [Member] \| Combination - Interest Rate Reduction and Term Extension \| Minimum [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Reduced weighted-average contractual interest rate	6.80%
Home Equity Loan [Member] \| Extended Maturity and Principal Forgiveness
Financing Receivable, Troubled Debt Restructuring [Line Items]
% of Total Class of Financing Receivable	0.01%	0.00%
Financing Receivable, Modified, Accumulated	$ 72	$ 0

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