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	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Financing Receivable Allowance For Credit Losses [Line Items]
Release of credit losses - unfunded commitments			$ (412)	$ (1,107)
Funded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Beginning Balance	$ 34,110	$ 35,646	34,496	36,016
Charge-offs	(6)		(31)	(3)
Recoveries	20	46	58	69
Provision for (release of) credit losses - loan portfolio		(663)	(399)	(1,053)
Allowance for credit losses-loan portfolio, Ending Balance	34,124	35,029	34,124	35,029
Unfunded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Beginning Balance	1,371	1,188	1,384	1,004
Release of credit losses - unfunded commitments		(238)	(13)	(54)
Allowance for credit losses-unfunded commitments	1,371	950	1,371	950
Allowance for credit losses-loan portfolio, Ending Balance	35,495	35,979	35,495	35,979
Residential Mortgage \| Funded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Beginning Balance	13,193	13,144	13,383	13,067
Provision for (release of) credit losses - loan portfolio	(554)	412	(744)	489
Allowance for credit losses-loan portfolio, Ending Balance	12,639	13,556	12,639	13,556
Residential Mortgage \| Unfunded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Ending Balance	12,639	13,556	12,639	13,556
Commercial Mortgage \| Funded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Beginning Balance	17,138	18,693	17,133	18,564
Recoveries		30		30
Provision for (release of) credit losses - loan portfolio	629	(1,422)	634	(1,293)
Allowance for credit losses-loan portfolio, Ending Balance	17,767	17,301	17,767	17,301
Commercial Mortgage \| Unfunded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Ending Balance	17,767	17,301	17,767	17,301
Home Equity \| Funded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Beginning Balance	377	363	406	552
Provision for (release of) credit losses - loan portfolio	23	110	(6)	(79)
Allowance for credit losses-loan portfolio, Ending Balance	400	473	400	473
Home Equity \| Unfunded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Ending Balance	400	473	400	473
Commercial & Industrial \| Funded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Beginning Balance	2,897	2,978	2,989	3,309
Charge-offs	(3)		(3)
Recoveries	10	15	46	34
Provision for (release of) credit losses - loan portfolio	(52)	216	(180)	(134)
Allowance for credit losses-loan portfolio, Ending Balance	2,852	3,209	2,852	3,209
Commercial & Industrial \| Unfunded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Ending Balance	2,852	3,209	2,852	3,209
Consumer \| Funded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Beginning Balance	505	468	585	524
Charge-offs	(3)		(28)	(3)
Recoveries	10	1	12	5
Provision for (release of) credit losses - loan portfolio	(46)	21	(103)	(36)
Allowance for credit losses-loan portfolio, Ending Balance	466	490	466	490
Consumer \| Unfunded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Ending Balance	466	490	466	490
Unfunded Commitments \| Unfunded Commitments
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses-loan portfolio, Beginning Balance	1,371	1,188	1,384	1,004
Release of credit losses - unfunded commitments		(238)	(13)	(54)
Allowance for credit losses-unfunded commitments	1,371	950	1,371	950
Allowance for credit losses-loan portfolio, Ending Balance	$ 1,371	$ 950	$ 1,371	$ 950

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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 of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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