Loan Credit Quality Analysis (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	$ 437,943	$ 419,974
Financing Receivable, Recorded Investment, Special Mention	3,337	3,319
Financing Receivable Recorded Investment, Substandard Accruing	5,790	5,843
Financing Receivable, Recorded Investment, Nonaccrual Status	2,902	2,370
Loans and Leases Receivable, Gross, Carrying Amount	449,972	431,506	$ 427,742
Commercial and Industrial Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	49,817	49,558
Financing Receivable, Recorded Investment, Special Mention	121	22
Financing Receivable Recorded Investment, Substandard Accruing	130	233
Financing Receivable, Recorded Investment, Nonaccrual Status	33	37
Loans and Leases Receivable, Gross, Carrying Amount	50,101	49,850	50,881
Construction And Land Development Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	46,778	41,165
Financing Receivable, Recorded Investment, Special Mention	404	113
Financing Receivable Recorded Investment, Substandard Accruing	273	340
Financing Receivable, Recorded Investment, Nonaccrual Status	0	32
Loans and Leases Receivable, Gross, Carrying Amount	47,455	41,650	44,004
Commercial Real Estate Owner Occupied Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	41,048	48,788
Financing Receivable, Recorded Investment, Special Mention	244	414
Financing Receivable Recorded Investment, Substandard Accruing	341	405
Financing Receivable, Recorded Investment, Nonaccrual Status	0	138
Loans and Leases Receivable, Gross, Carrying Amount	41,633	49,745
Commercial Real Estate Multifamily [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	47,794	46,998
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	47,794	46,998
Commercial Real Estate Other Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	139,671	121,326
Financing Receivable, Recorded Investment, Special Mention	356	32
Financing Receivable Recorded Investment, Substandard Accruing	426	449
Financing Receivable, Recorded Investment, Nonaccrual Status	2,500	1,889
Loans and Leases Receivable, Gross, Carrying Amount	142,953	123,696
Commercial Real Estate Loans, Total [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	228,513	217,112
Financing Receivable, Recorded Investment, Special Mention	600	446
Financing Receivable Recorded Investment, Substandard Accruing	767	854
Financing Receivable, Recorded Investment, Nonaccrual Status	2,500	2,027
Loans and Leases Receivable, Gross, Carrying Amount	232,380	220,439	211,558
Residential Real Estate Consumer Mortgage Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	57,087	59,450
Financing Receivable, Recorded Investment, Special Mention	2,032	2,613
Financing Receivable Recorded Investment, Substandard Accruing	3,584	3,278
Financing Receivable, Recorded Investment, Nonaccrual Status	353	223
Loans and Leases Receivable, Gross, Carrying Amount	63,056	65,564
Residential Real Estate Investment Property Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	46,054	44,109
Financing Receivable, Recorded Investment, Special Mention	109	105
Financing Receivable Recorded Investment, Substandard Accruing	940	1,048
Financing Receivable, Recorded Investment, Nonaccrual Status	0	29
Loans and Leases Receivable, Gross, Carrying Amount	47,103	45,291
Residential Real Estate Loans, Total [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	103,141	103,559
Financing Receivable, Recorded Investment, Special Mention	2,141	2,718
Financing Receivable Recorded Investment, Substandard Accruing	4,524	4,326
Financing Receivable, Recorded Investment, Nonaccrual Status	353	252
Loans and Leases Receivable, Gross, Carrying Amount	110,159	110,855	112,303
Consumer Installment and Revolving Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Pass	9,694	8,580
Financing Receivable, Recorded Investment, Special Mention	71	20
Financing Receivable Recorded Investment, Substandard Accruing	96	90
Financing Receivable, Recorded Investment, Nonaccrual Status	16	22
Loans and Leases Receivable, Gross, Carrying Amount	$ 9,877	$ 8,712	$ 8,996