Shareholders' Equity, Compliance with Regulatory Capital Requirements (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Total Capital to Risk Weighted Assets [Abstract]
Actual Amount	$ 346,845	$ 342,210
Current Regulatory Capital Requirement, Amount	$ 243,459	$ 209,532
Total Capital to Risk Weighted Assets, Ratio [Abstract]
Actual Ratio	11.40%	13.07%
Current Regulatory Capital Requirement, Ratio	8.00%	8.00%
Total Common Equity Tier 1 Capital [Abstract]
Actual Amount	$ 298,588	$ 299,401
Current Regulatory Capital Requirement, Amount	$ 136,945	$ 117,862
Total Common Equity Tier 1 Capital, Ratio [Abstract]
Actual Ratio	9.81%	11.43%
Current Regulatory Capital Requirement, Ratio	4.50%	4.50%
Tier 1 Capital to Risk Weighted Assets [Abstract]
Actual Amount	$ 308,588	$ 309,250
Current Regulatory Capital Requirement, Amount	$ 182,594	$ 157,150
Tier 1 Capital to Risk Weighted Assets, Ratio [Abstract]
Actual Ratio	10.14%	11.81%
Current Regulatory Capital Requirement Ratio	6.00%	6.00%
Tier 1 Capital to Average Assets [Abstract]
Actual Amount	$ 308,588	$ 309,250
Current Regulatory Capital Requirement, Amount	$ 135,949	$ 123,790
Tier 1 Capital to Average Assets, Ratio [Abstract]
Actual Ratio	9.08%	9.99%
Current Regulatory Capital Requirement, Ratio	3.00%	4.00%
Bank [Member]
Total Capital to Risk Weighted Assets [Abstract]
Actual Amount	$ 346,763	$ 330,041
Current Regulatory Capital Requirement, Amount	243,455	208,552
Well Capitalized Under Prompt Corrective Action, Amount	$ 304,319	$ 260,691
Total Capital to Risk Weighted Assets, Ratio [Abstract]
Actual Ratio	11.39%	12.66%
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	$ 308,507	$ 297,232
Current Regulatory Capital Requirement, Amount	136,944	117,311
Well Capitalized Under Prompt Corrective Action, Amount	$ 197,807	$ 169,449
Total Common Equity Tier 1 Capital, Ratio [Abstract]
Actual Ratio	10.14%	11.40%
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	$ 308,507	$ 297,232
Current Regulatory Capital Requirement, Amount	182,591	156,414
Well Capitalized Under Prompt Corrective Action, Amount	$ 243,455	$ 208,552
Tier 1 Capital to Risk Weighted Assets, Ratio [Abstract]
Actual Ratio	10.14%	11.40%
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	$ 308,507	$ 297,232
Current Regulatory Capital Requirement, Amount	134,822	123,178
Well Capitalized Under Prompt Corrective Action, Amount	$ 168,527	$ 153,972
Tier 1 Capital to Average Assets, Ratio [Abstract]
Actual Ratio	9.15%	9.65%
Current Regulatory Capital Requirement, Ratio	3.00%	4.00%
Well Capitalized Under Prompt Corrective Action, Ratio	5.00%	5.00%

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The amount of total capital as defined in the regulations.

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The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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Amount of Common Equity Tier One Risk-based Capital, as defined by regulatory framework.

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Percentage of Common Equity Tier One Risk-based Capital to total risk-weighted assets, as defined by regulatory framework.

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Amount of Common Equity Tier 1 Risk-based Capital required to be categorized as adequately capitalized under regulatory framework for prompt corrective action.

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