Regulatory Capital (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Regulatory Assets
Common Equity	$ 109,957	$ 104,426
Total stockholders' equity	109,957	104,426	$ 99,783	$ 116,559
AOCI Losses (Gains)	1,191	928	251	378
Common equity Tier 1 capital	111,148	105,354
TRUPs	12,000	12,000
Tier 1 capital	123,148	117,354
Allowable reserve for credit losses and other Tier 2 adjustments	10,545	9,860
Subordinated notes	23,000	23,000
Tier 2 capital	156,693	150,214
Risk-weighted assets ("RWA")	1,169,341	1,104,505
Average Assets ("AA")	$ 1,401,741	$ 1,300,445
Common Tier 1 capital to RWA, 2019 Regulatory Min. Ratio + CCB	7.00%
Tier 1 capital to RWA, 2019 Regulatory Min. Ratio + CCB	8.50%
Tier 2 capital to RWA, 2019 Regulatory Min. Ratio + CCB	10.50%
Common Tier 1 capital to RWA	9.51%	9.54%
Tier 1 capital to RWA	10.53%	10.62%
Tier 2 capital to RWA	13.40%	13.60%
Tier 1 capital to AA (leverage)	8.79%	9.02%
Common Stock [Member]
Regulatory Assets
Total stockholders' equity	$ 46	$ 46	$ 46	47
SBLF Preferred Stock [Member]
Regulatory Assets
Total stockholders' equity				$ 20,000
Bank [Member]
Regulatory Assets
Common Equity	139,046	136,109
AOCI Losses (Gains)	1,191	928
Common equity Tier 1 capital	140,237	137,037
Tier 1 capital	140,237	137,037
Allowable reserve for credit losses and other Tier 2 adjustments	10,545	9,860
Tier 2 capital	150,782	146,897
Risk-weighted assets ("RWA")	1,164,478	1,102,116
Average Assets ("AA")	$ 1,398,001	$ 1,298,145
Common Tier 1 capital to RWA	12.04%	12.43%
Tier 1 capital to RWA	12.04%	12.43%
Tier 2 capital to RWA	12.95%	13.33%
Tier 1 capital to AA (leverage)	10.03%	10.56%