Loan Credit Quality Analysis (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	$ 448,028	$ 443,362
Financing Receivable, Recorded Investment, Special Mention	6,347	2,192
Financing Receivable Recorded Investment, Substandard Accruing	5,651	5,651
Financing Receivable, Recorded Investment, Nonaccrual Status	934	2,972
Loans and Leases Receivable, Gross, Carrying Amount	460,960	454,177	$ 449,972
Commercial and Industrial Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	50,137	58,842
Financing Receivable, Recorded Investment, Special Mention	2,197	94
Financing Receivable Recorded Investment, Substandard Accruing	96	119
Financing Receivable, Recorded Investment, Nonaccrual Status	0	31
Loans and Leases Receivable, Gross, Carrying Amount	52,430	59,086	50,101
Construction And Land Development Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	44,257	39,049
Financing Receivable, Recorded Investment, Special Mention	53	90
Financing Receivable Recorded Investment, Substandard Accruing	763	468
Financing Receivable, Recorded Investment, Nonaccrual Status	36	0
Loans and Leases Receivable, Gross, Carrying Amount	45,109	39,607	47,455
Commercial Real Estate Owner Occupied Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	51,138	43,615
Financing Receivable, Recorded Investment, Special Mention	387	240
Financing Receivable Recorded Investment, Substandard Accruing	321	337
Financing Receivable, Recorded Investment, Nonaccrual Status	0	0
Loans and Leases Receivable, Gross, Carrying Amount	51,846	44,192
Commercial Real Estate Multifamily [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	40,753	52,167
Financing Receivable, Recorded Investment, Special Mention	0	0
Financing Receivable Recorded Investment, Substandard Accruing	0	0
Financing Receivable, Recorded Investment, Nonaccrual Status	0	0
Loans and Leases Receivable, Gross, Carrying Amount	40,753	52,167
Commercial Real Estate Other Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	155,490	139,695
Financing Receivable, Recorded Investment, Special Mention	988	395
Financing Receivable Recorded Investment, Substandard Accruing	377	396
Financing Receivable, Recorded Investment, Nonaccrual Status	696	2,188
Loans and Leases Receivable, Gross, Carrying Amount	157,551	142,674
Commercial Real Estate Loans, Total [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	247,381	235,477
Financing Receivable, Recorded Investment, Special Mention	1,375	635
Financing Receivable Recorded Investment, Substandard Accruing	698	733
Financing Receivable, Recorded Investment, Nonaccrual Status	696	2,188
Loans and Leases Receivable, Gross, Carrying Amount	250,150	239,033	232,380
Residential Real Estate Consumer Mortgage Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	51,236	54,101
Financing Receivable, Recorded Investment, Special Mention	2,439	1,254
Financing Receivable Recorded Investment, Substandard Accruing	3,274	3,586
Financing Receivable, Recorded Investment, Nonaccrual Status	194	599
Loans and Leases Receivable, Gross, Carrying Amount	57,143	59,540
Residential Real Estate Investment Property Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	45,231	46,463
Financing Receivable, Recorded Investment, Special Mention	204	53
Financing Receivable Recorded Investment, Substandard Accruing	751	667
Financing Receivable, Recorded Investment, Nonaccrual Status	0	140
Loans and Leases Receivable, Gross, Carrying Amount	46,186	47,323
Residential Real Estate Loans, Total [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	96,467	100,564
Financing Receivable, Recorded Investment, Special Mention	2,643	1,307
Financing Receivable Recorded Investment, Substandard Accruing	4,025	4,253
Financing Receivable, Recorded Investment, Nonaccrual Status	194	739
Loans and Leases Receivable, Gross, Carrying Amount	103,329	106,863	110,159
Consumer Installment and Revolving Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	9,786	9,430
Financing Receivable, Recorded Investment, Special Mention	79	66
Financing Receivable Recorded Investment, Substandard Accruing	69	78
Financing Receivable, Recorded Investment, Nonaccrual Status	8	14
Loans and Leases Receivable, Gross, Carrying Amount	$ 9,942	$ 9,588	$ 9,877