Loans Loan Categories and Past Due Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018
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	11,399	13,177	12,999
Current Loans	2,324,192	2,183,038	2,113,101
Total Loans	2,335,591	2,196,215	2,126,100
Loans 90 or More Days Past Due and Still Accruing Interest	1,066	1,225	1,172
Nonaccrual Loans	3,465	4,159	4,468
Financing Receivables, 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	5,556	5,879	8,745
Financing Receivables, 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	2,713	4,093	1,354
Financing Receivables, Equal to Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	3,130	3,205	2,900
Commercial
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	147	170	274
Current Loans	141,988	136,720	126,838
Total Loans	142,135	136,890	127,112
Loans 90 or More Days Past Due and Still Accruing Interest	0	0	0
Nonaccrual Loans	28	403	674
Commercial \| Financing Receivables, 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	99	121	198
Commercial \| Financing Receivables, 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	48	49	0
Commercial \| Financing Receivables, Equal to Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	0	0	76
Commercial Real Estate Portfolio Segment
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	358	897	807
Current Loans	497,725	483,665	469,315
Total Loans	498,083	484,562	470,122
Loans 90 or More Days Past Due and Still Accruing Interest	0	0	0
Nonaccrual Loans	465	789	807
Commercial Real Estate Portfolio Segment \| Financing Receivables, 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	0	108	0
Commercial Real Estate Portfolio Segment \| Financing Receivables, 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	30	0	0
Commercial Real Estate Portfolio Segment \| Financing Receivables, Equal to Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	328	789	807
Consumer Loans Financing
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	7,255	8,077	7,452
Current Loans	798,542	711,433	686,736
Total Loans	805,797	719,510	694,188
Loans 90 or More Days Past Due and Still Accruing Interest	86	144	192
Nonaccrual Loans	564	658	540
Consumer Loans Financing \| Financing Receivables, 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	5,216	5,369	5,651
Consumer Loans Financing \| Financing Receivables, 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	1,624	2,136	1,307
Consumer Loans Financing \| Financing Receivables, Equal to Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	415	572	494
Residential
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	3,639	4,033	4,466
Current Loans	885,937	851,220	830,212
Total Loans	889,576	855,253	834,678
Loans 90 or More Days Past Due and Still Accruing Interest	980	1,081	980
Nonaccrual Loans	2,408	2,309	2,447
Residential \| Financing Receivables, 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	241	281	2,896
Residential \| Financing Receivables, 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	1,011	1,908	47
Residential \| Financing Receivables, Equal to Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded investment, past due	$ 2,387	$ 1,844	$ 1,523

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

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