Loans and the Allowance for Credit Losses - Schedule of Loans Receivable Disaggregated by Past Due Status (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	$ 4,001,202	$ 4,046,250
Total loans	4,027,967	4,062,856
30-59 Days Past Due
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	22,055	12,467
60-89 Days Past Due
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	1,455	2,116
90 Days or Greater
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	3,255	2,023
Total Past Due
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	26,765	16,606
Residential Mortgage
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	1,603,274	1,634,216
Total loans	1,627,460	1,648,838
Residential Mortgage | 30-59 Days Past Due
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	20,158	11,359
Residential Mortgage | 60-89 Days Past Due
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	1,064	1,454
Residential Mortgage | 90 Days or Greater
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	2,964	1,809
Residential Mortgage | Total Past Due
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	24,186	14,622
Commercial Mortgage
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	1,921,788	1,914,423
Total loans	1,922,455	1,914,423
Commercial Mortgage | 30-59 Days Past Due
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	667
Commercial Mortgage | Total Past Due
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	667
Home Equity
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	91,852	109,782
Total loans	93,364	111,351
Home Equity | 30-59 Days Past Due
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	1,202	962
Home Equity | 60-89 Days Past Due
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	28	393
Home Equity | 90 Days or Greater
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	282	214
Home Equity | Total Past Due
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	1,512	1,569
Commercial and Industrial
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	355,403	350,316
Total loans	355,796	350,650
Commercial and Industrial | 30-59 Days Past Due
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	21	65
Commercial and Industrial | 60-89 Days Past Due
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	363	269
Commercial and Industrial | 90 Days or Greater
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	9
Commercial and Industrial | Total Past Due
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	393	334
Consumer
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	28,885	37,513
Total loans	28,892	37,594
Consumer | 30-59 Days Past Due
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	7	81
Consumer | Total Past Due
Financing Receivable Allowance For Credit Losses [Line Items]
Total Principal Balance/Past Due	$ 7	$ 81