Loans Past Due Analysis (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Current	$ 440,236	$ 450,082
Financing Receivable, Recorded Investment, 30 To 89 Days Past Due	838	1,123
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	0	0
Financing Receivable, Recorded Investment, Total Still Accruing	441,074	451,205
Financing Receivable, Recorded Investment, Nonaccrual Status	3,239	2,972
Loans and Leases Receivable, Gross, Carrying Amount	444,313	454,177	$ 431,193
Commercial and Industrial Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Current	57,640	59,047
Financing Receivable, Recorded Investment, 30 To 89 Days Past Due	3	8
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	0	0
Financing Receivable, Recorded Investment, Total Still Accruing	57,643	59,055
Financing Receivable, Recorded Investment, Nonaccrual Status	234	31
Loans and Leases Receivable, Gross, Carrying Amount	57,877	59,086	50,228
Construction And Land Development Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Current	35,657	39,607
Financing Receivable, Recorded Investment, 30 To 89 Days Past Due	253	0
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	0	0
Financing Receivable, Recorded Investment, Total Still Accruing	35,910	39,607
Financing Receivable, Recorded Investment, Nonaccrual Status	0	0
Loans and Leases Receivable, Gross, Carrying Amount	35,910	39,607	45,098
Commercial Real Estate Owner Occupied Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Current	43,467	44,192
Financing Receivable, Recorded Investment, 30 To 89 Days Past Due	0	0
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	0	0
Financing Receivable, Recorded Investment, Total Still Accruing	43,467	44,192
Financing Receivable, Recorded Investment, Nonaccrual Status	0	0
Loans and Leases Receivable, Gross, Carrying Amount	43,467	44,192
Commercial Real Estate Multifamily [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Current	40,060	52,167
Financing Receivable, Recorded Investment, 30 To 89 Days Past Due	0	0
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	0	0
Financing Receivable, Recorded Investment, Total Still Accruing	40,060	52,167
Financing Receivable, Recorded Investment, Nonaccrual Status	0	0
Loans and Leases Receivable, Gross, Carrying Amount	40,060	52,167
Commercial Real Estate Other Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Current	148,355	140,486
Financing Receivable, Recorded Investment, 30 To 89 Days Past Due	0	0
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	0	0
Financing Receivable, Recorded Investment, Total Still Accruing	148,355	140,486
Financing Receivable, Recorded Investment, Nonaccrual Status	2,463	2,188
Loans and Leases Receivable, Gross, Carrying Amount	150,818	142,674
Commercial Real Estate Loans, Total [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Current	231,882	236,845
Financing Receivable, Recorded Investment, 30 To 89 Days Past Due	0	0
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	0	0
Financing Receivable, Recorded Investment, Total Still Accruing	231,882	236,845
Financing Receivable, Recorded Investment, Nonaccrual Status	2,463	2,188
Loans and Leases Receivable, Gross, Carrying Amount	234,345	239,033	218,739
Residential Real Estate Consumer Mortgage Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Current	58,142	58,195
Financing Receivable, Recorded Investment, 30 To 89 Days Past Due	442	746
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	0	0
Financing Receivable, Recorded Investment, Total Still Accruing	58,584	58,941
Financing Receivable, Recorded Investment, Nonaccrual Status	530	599
Loans and Leases Receivable, Gross, Carrying Amount	59,114	59,540
Residential Real Estate Investment Property Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Current	47,251	46,871
Financing Receivable, Recorded Investment, 30 To 89 Days Past Due	131	312
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	0	0
Financing Receivable, Recorded Investment, Total Still Accruing	47,382	47,183
Financing Receivable, Recorded Investment, Nonaccrual Status	0	140
Loans and Leases Receivable, Gross, Carrying Amount	47,382	47,323
Residential Real Estate Loans, Total [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Current	105,393	105,066
Financing Receivable, Recorded Investment, 30 To 89 Days Past Due	573	1,058
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	0	0
Financing Receivable, Recorded Investment, Total Still Accruing	105,966	106,124
Financing Receivable, Recorded Investment, Nonaccrual Status	530	739
Loans and Leases Receivable, Gross, Carrying Amount	106,496	106,863	108,096
Consumer Installment and Revolving Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Current	9,664	9,517
Financing Receivable, Recorded Investment, 30 To 89 Days Past Due	9	57
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	0	0
Financing Receivable, Recorded Investment, Total Still Accruing	9,673	9,574
Financing Receivable, Recorded Investment, Nonaccrual Status	12	14
Loans and Leases Receivable, Gross, Carrying Amount	$ 9,685	$ 9,588	$ 9,032