Loans - Loan Categories and Past Due Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Financing Receivable, Recorded Investment, Aging [Abstract]
Loans receivable held-for-sale, net, not part of disposal group	$ 4,443	$ 11,085	$ 1,905
Recorded investment, past due	12,075	13,783	12,736
Current Loans	2,627,168	2,581,247	2,401,457
Total	2,639,243	2,595,030	2,414,193
Loans 90 or More Days Past Due and Still Accruing Interest	242	228	437
Nonaccrual Loans	8,087	6,033	4,943
Nonaccrual With No Allowance for Credit Loss	5,364
Interest Income on Nonaccrual Loans	0
Commercial
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	135	293	251
Current Loans	288,416	240,261	146,849
Total	288,551	240,554	147,100
Loans 90 or More Days Past Due and Still Accruing Interest	0	0	5
Nonaccrual Loans	64	78	63
Nonaccrual With No Allowance for Credit Loss	64
Interest Income on Nonaccrual Loans	0
Commercial Real Estate
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	4,340	1,658	1,482
Current Loans	577,167	570,129	524,648
Total	581,507	571,787	526,130
Loans 90 or More Days Past Due and Still Accruing Interest	0	184	238
Nonaccrual Loans	4,364	1,475	1,445
Nonaccrual With No Allowance for Credit Loss	1,641
Interest Income on Nonaccrual Loans	14
Consumer
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	3,647	9,068	7,636
Current Loans	857,524	850,700	817,073
Total	861,171	859,768	824,709
Loans 90 or More Days Past Due and Still Accruing Interest	0	0	93
Nonaccrual Loans	746	1,470	715
Nonaccrual With No Allowance for Credit Loss	746
Interest Income on Nonaccrual Loans	0
Residential
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	3,953	2,764	3,367
Current Loans	904,061	920,157	912,887
Total	908,014	922,921	916,254
Loans 90 or More Days Past Due and Still Accruing Interest	242	44	101
Nonaccrual Loans	2,913	3,010	2,720
Nonaccrual With No Allowance for Credit Loss	2,913
Interest Income on Nonaccrual Loans	0
Financing Receivables, 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	4,536	5,339	7,900
Financing Receivables, 30 to 59 Days Past Due \| Commercial
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	63	102	173
Financing Receivables, 30 to 59 Days Past Due \| Commercial Real Estate
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	143	0	461
Financing Receivables, 30 to 59 Days Past Due \| Consumer
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	2,233	4,976	5,636
Financing Receivables, 30 to 59 Days Past Due \| Residential
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	2,097	261	1,630
Financing Receivables, 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	3,735	4,105	1,843
Financing Receivables, 60 to 89 Days Past Due \| Commercial
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	34	113	70
Financing Receivables, 60 to 89 Days Past Due \| Commercial Real Estate
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	2,723	0	110
Financing Receivables, 60 to 89 Days Past Due \| Consumer
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	822	2,713	1,451
Financing Receivables, 60 to 89 Days Past Due \| Residential
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	156	1,279	212
Financing Receivables, Equal to Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	3,804	4,339	2,993
Financing Receivables, Equal to Greater than 90 Days Past Due \| Commercial
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	38	78	8
Financing Receivables, Equal to Greater than 90 Days Past Due \| Commercial Real Estate
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	1,474	1,658	911
Financing Receivables, Equal to Greater than 90 Days Past Due \| Consumer
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	592	1,379	549
Financing Receivables, Equal to Greater than 90 Days Past Due \| Residential
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	$ 1,700	$ 1,224	$ 1,525

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Amount of financing receivable 90 days or more past due and still accruing.

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