Loans Loan Categories and Past Due Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Financing Receivable, Recorded Investment, Aging [Abstract]
Loans receivable held-for-sale, net, not part of disposal group	$ 1,905	$ 215	$ 201
Recorded investment, past due	12,736	13,606	10,177
Current Loans	2,401,457	2,372,514	2,225,031
Total Loans	2,414,193	2,386,120	2,235,208
Loans 90 or More Days Past Due and Still Accruing Interest	437	253	64
Nonaccrual Loans	4,943	4,005	5,143
Financing Receivables, 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	7,900	5,972	6,479
Financing Receivables, 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	1,843	5,035	1,594
Financing Receivables, Equal to Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	2,993	2,599	2,104
Commercial
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	251	213	185
Current Loans	146,849	150,447	133,091
Total Loans	147,100	150,660	133,276
Loans 90 or More Days Past Due and Still Accruing Interest	5	0	0
Nonaccrual Loans	63	81	415
Commercial \| Financing Receivables, 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	173	150	168
Commercial \| Financing Receivables, 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	70	42	0
Commercial \| Financing Receivables, Equal to Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	8	21	17
Commercial Real Estate
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	1,482	592	316
Current Loans	524,648	509,949	493,071
Total Loans	526,130	510,541	493,387
Loans 90 or More Days Past Due and Still Accruing Interest	238	0	0
Nonaccrual Loans	1,445	326	248
Commercial Real Estate \| Financing Receivables, 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	461	0	208
Commercial Real Estate \| Financing Receivables, 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	110	266	0
Commercial Real Estate \| Financing Receivables, Equal to Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	911	326	108
Consumer
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	7,636	8,815	6,514
Current Loans	817,073	802,383	740,285
Total Loans	824,709	811,198	746,799
Loans 90 or More Days Past Due and Still Accruing Interest	93	0	0
Nonaccrual Loans	715	663	588
Consumer \| Financing Receivables, 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	5,636	5,670	4,758
Consumer \| Financing Receivables, 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	1,451	2,700	1,387
Consumer \| Financing Receivables, Equal to Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	549	445	369
Residential
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	3,367	3,986	3,162
Current Loans	912,887	909,735	858,584
Total Loans	916,254	913,721	861,746
Loans 90 or More Days Past Due and Still Accruing Interest	101	253	64
Nonaccrual Loans	2,720	2,935	3,892
Residential \| Financing Receivables, 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	1,630	152	1,345
Residential \| Financing Receivables, 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	212	2,027	207
Residential \| Financing Receivables, Equal to Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	$ 1,525	$ 1,807	$ 1,610

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

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