Loans and the Allowance for Credit Losses - Summary of Changes in Allowance for Credit Losses Disaggregated by Loan Category (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Financing Receivable Allowance For Credit Losses [Line Items]
Provision for (release of) credit losses - unfunded commitments			$ 335	$ 200
Allowance for credit losses-loan portfolio, Ending Balance	$ 40,125	$ 36,117	40,125	36,117
Funded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Beginning Balance	38,073	34,124	37,774	34,496
Charge-offs	(87)		(123)	(31)
Recoveries	13	10	43	68
Provision for (release of) credit losses - loan portfolio	195	614	500	(215)
Provision for (release of) credit losses - unfunded commitments		(2)
Allowance for credit losses-loan portfolio, Ending Balance	38,194	34,748	38,194	34,748
Unfunded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Beginning Balance	1,931	1,371	2,096	1,384
Provision for (release of) credit losses - unfunded commitments			(165)	(15)
Allowance for credit losses-unfunded commitments	1,931	1,369	1,931	1,369
Allowance for credit losses-loan portfolio, Ending Balance	40,125	36,117	40,125	36,117
Residential Mortgage \| Funded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Beginning Balance	13,597	12,639	13,321	13,383
Provision for (release of) credit losses - loan portfolio	(4,676)	604	(4,400)	(140)
Allowance for credit losses-loan portfolio, Ending Balance	8,921	13,243	8,921	13,243
Residential Mortgage \| Unfunded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Ending Balance	8,921	13,243	8,921	13,243
Commercial Mortgage \| Funded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Beginning Balance	19,299	17,767	19,086	17,133
Provision for (release of) credit losses - loan portfolio	3,665	(538)	3,878	96
Allowance for credit losses-loan portfolio, Ending Balance	22,964	17,229	22,964	17,229
Commercial Mortgage \| Unfunded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Ending Balance	22,964	17,229	22,964	17,229
Home Equity \| Funded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Beginning Balance	468	400	573	406
Provision for (release of) credit losses - loan portfolio	150	48	45	42
Allowance for credit losses-loan portfolio, Ending Balance	618	448	618	448
Home Equity \| Unfunded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Ending Balance	618	448	618	448
Commercial & Industrial \| Funded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Beginning Balance	4,252	2,852	4,153	2,989
Charge-offs	(51)		(62)	(3)
Recoveries	9	10	28	56
Provision for (release of) credit losses - loan portfolio	843	549	934	369
Allowance for credit losses-loan portfolio, Ending Balance	5,053	3,411	5,053	3,411
Commercial & Industrial \| Unfunded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Ending Balance	5,053	3,411	5,053	3,411
Consumer \| Funded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Beginning Balance	457	466	641	585
Charge-offs	(36)		(61)	(28)
Recoveries	4		15	12
Provision for (release of) credit losses - loan portfolio	213	(49)	43	(152)
Allowance for credit losses-loan portfolio, Ending Balance	638	417	638	417
Consumer \| Unfunded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Ending Balance	638	417	638	417
Unfunded Commitments \| Unfunded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Beginning Balance	1,931	1,371	2,096	1,384
Provision for (release of) credit losses - unfunded commitments		(2)	(165)	(15)
Allowance for credit losses-unfunded commitments	1,931	1,369	1,931	1,369
Allowance for credit losses-loan portfolio, Ending Balance	$ 1,931	$ 1,369	$ 1,931	$ 1,369

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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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