Regulatory Matters - Schedule of Regulatory Capital (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Total capital to risk-weighted assets: Amount
Actual	$ 64,221	$ 58,605
For capital adequacy purposes	39,630	35,424
To be well capitalized	49,537	44,280
Tier 1 capital to risk-weighted assets: Amount
Actual	58,088	53,050
For capital adequacy purposes	29,722	26,568
To be well capitalized	39,630	35,424
Common Equity Tier 1 capital to risk-weighted assets: Amount
Actual	58,088	53,050
For capital adequacy purposes	22,292	19,926
To be well capitalized	32,199	28,782
Tier 1 capital to average assets: Amount
Actual	58,088	53,050
For capital adequacy purposes	30,117	27,081
To be well capitalized	$ 37,647	$ 33,852
Total capital to risk-weighted assets: Ratio
Actual	12.96%	13.23%
For capital adequacy purposes	8.00%	8.00%
To be well capitalized	10.00%	10.00%
Tier 1 capital to risk-weighted assets: Ratios
Actual	11.73%	11.98%
For capital adequacy purposes	6.00%	6.00%
To be well capitalized	8.00%	8.00%
Common Equity Tier One Risk Based Capital To Risk Weighted Assets, Amount [Abstract]
Actual	11.73%	11.98%
For capital adequacy purposes	4.50%	4.50%
To be well capitalized	6.50%	6.50%
Tier 1 capital to average assets: Ratio
Actual	7.71%	7.84%
For capital adequacy purposes	4.00%	4.00%
To be well capitalized	5.00%	5.00%