Shareholders' Equity, Compliance with Regulatory Capital Requirements (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Total Capital to Risk Weighted Assets [Abstract]
Actual Amount	$ 319,983	$ 291,152
Current Regulatory Capital Requirement, Amount	$ 199,981	$ 190,493
Total Capital to Risk Weighted Assets, Ratio [Abstract]
Actual Ratio	12.80%	12.23%
Current Regulatory Capital Requirement, Ratio	8.00%	8.00%
Total Common Equity Tier 1 Capital [Abstract]
Actual Amount	$ 278,981	$ 251,240
Current Regulatory Capital Requirement, Amount	$ 112,489	$ 107,152
Total Common Equity Tier 1 Capital, Ratio [Abstract]
Actual Ratio	11.16%	10.55%
Current Regulatory Capital Requirement, Ratio	4.50%	4.50%
Tier 1 Capital to Risk Weighted Assets [Abstract]
Actual Amount	$ 288,527	$ 261,240
Current Regulatory Capital Requirement, Amount	$ 149,986	$ 142,870
Tier 1 Capital to Risk Weighted Assets, Ratio [Abstract]
Actual Ratio	11.54%	10.97%
Current Regulatory Capital Requirement Ratio	6.00%	6.00%
Tier 1 Capital to Average Assets [Abstract]
Actual Amount	$ 288,527	$ 261,240
Current Regulatory Capital Requirement, Amount	$ 114,568	$ 101,525
Tier 1 Capital to Average Assets, Ratio [Abstract]
Actual Ratio	10.07%	10.29%
Current Regulatory Capital Requirement, Ratio	4.00%	4.00%
Bank [Member]
Total Capital to Risk Weighted Assets [Abstract]
Actual Amount	$ 319,776	$ 290,941
Current Regulatory Capital Requirement, Amount	199,958	190,480
Well Capitalized Under Prompt Corrective Action, Amount	$ 249,947	$ 238,101
Total Capital to Risk Weighted Assets, Ratio [Abstract]
Actual Ratio	12.79%	12.22%
Current Regulatory Capital Requirement, Ratio	8.00%	8.00%
Well Capitalized Under Prompt Corrective Action, Ratio	10.00%	10.00%
Total Common Equity Tier 1 Capital [Abstract]
Actual Amount	$ 288,324	$ 261,031
Current Regulatory Capital Requirement, Amount	112,476	107,145
Well Capitalized Under Prompt Corrective Action, Amount	$ 162,466	$ 154,765
Total Common Equity Tier 1 Capital, Ratio [Abstract]
Actual Ratio	11.54%	10.96%
Current Regulatory Capital Requirement, Ratio	4.50%	4.50%
Well Capitalized Under Prompt Corrective Action, Ratio	6.50%	6.50%
Tier 1 Capital to Risk Weighted Assets [Abstract]
Actual Amount	$ 288,323	$ 261,031
Current Regulatory Capital Requirement, Amount	149,968	142,860
Well Capitalized Under Prompt Corrective Action, Amount	$ 199,958	$ 190,480
Tier 1 Capital to Risk Weighted Assets, Ratio [Abstract]
Actual Ratio	11.54%	10.96%
Current Regulatory Capital Requirement Ratio	6.00%	6.00%
Well Capitalized Under Prompt Corrective Action, Ratio	8.00%	8.00%
Tier 1 Capital to Average Assets [Abstract]
Actual Amount	$ 288,324	$ 261,031
Current Regulatory Capital Requirement, Amount	114,409	101,402
Well Capitalized Under Prompt Corrective Action, Amount	$ 143,011	$ 126,753
Tier 1 Capital to Average Assets, Ratio [Abstract]
Actual Ratio	10.08%	10.30%
Current Regulatory Capital Requirement, Ratio	4.00%	4.00%
Well Capitalized Under Prompt Corrective Action, Ratio	5.00%	5.00%