Regulatory Capital Matters (Details)	Sep. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)
Common equity tier 1 to risk-weighted assets:
Actual capital, amount	$ 139,067,000	$ 157,659,000
Actual capital, ratio	0.0883	0.1172
Required capital adequacy, amount	$ 70,875,000	$ 60,533,000
Required capital adequacy, ratio	4.50%	4.50%
Required capital adequacy with capital conservation buffer, amount	$ 110,250,000	$ 94,163,000
Required capital adequacy with capital conservation buffer, ratio	7.00%	7.00%
Tier 1 capital to risk-weighted assets:
Actual capital, amount	$ 162,437,000	$ 157,659,000
Actual capital, ratio	0.1031	0.1172
Required capital adequacy, amount	$ 94,500,000	$ 80,711,000
Required capital adequacy, ratio	0.0600	0.0600
Required capital adequacy with capital conservation buffer, amount	$ 133,875,000	$ 114,341,000
Required capital adequacy, ratio	8.50%	8.50%
Total capital to risk-weighted assets:
Actual capital, amount	$ 226,679,000	$ 215,091,000
Actual capital, ratio	0.1439	0.1599
Required capital adequacy, amount	$ 126,000,000	$ 107,615,000
Required capital adequacy, ratio	0.0800	0.0800
Required capital adequacy with capital conservation buffer, amount	$ 165,375,000	$ 141,244,000
Required capital adequacy, ratio	10.50%	10.50%
Tier 1 capital to average assets (leverage ratio):
Actual capital, amount	$ 162,437,000	$ 157,659,000
Actual capital, ratio	0.0717	0.1041
Required capital adequacy, amount	$ 90,664,000	$ 60,580,000
Required capital adequacy, ratio	0.0400	0.0400
Required capital adequacy with capital conservation buffer, amount	$ 90,664,000	$ 60,580,000
Required capital adequacy with capital conservation buffer, ratio	4.00%	4.00%
Capital conservation buffer, percentage	2.50%	2.50%
Amount available for dividend payment without regulatory approval	$ 42,900,000
Bank
Common equity tier 1 to risk-weighted assets:
Actual capital, amount	$ 176,593,000	$ 165,199,000
Actual capital, ratio	0.1123	0.1227
Required capital adequacy, amount	$ 70,760,000	$ 60,568,000
Required capital adequacy, ratio	4.50%	4.50%
Required capital adequacy with capital conservation buffer, amount	$ 110,070,000	$ 94,217,000
Required capital adequacy with capital conservation buffer, ratio	7.00%	7.00%
Prompt corrective action provisions, amount	$ 102,208,000	$ 87,487,000
Prompt corrective action provisions, ratio	6.50%	6.50%
Tier 1 capital to risk-weighted assets:
Actual capital, amount	$ 176,593,000	$ 165,199,000
Actual capital, ratio	0.1123	0.1227
Required capital adequacy, amount	$ 94,346,000	$ 80,757,000
Required capital adequacy, ratio	0.0600	0.0600
Required capital adequacy with capital conservation buffer, amount	$ 133,657,000	$ 114,406,000
Required capital adequacy, ratio	8.50%	8.50%
Prompt corrective action provisions, amount	$ 125,795,000	$ 107,676,000
Prompt corrective action provisions, ratio	0.0800	0.0800
Total capital to risk-weighted assets:
Actual capital, amount	$ 196,274,000	$ 178,191,000
Actual capital, ratio	0.1248	0.1324
Required capital adequacy, amount	$ 125,795,000	$ 107,676,000
Required capital adequacy, ratio	0.0800	0.0800
Required capital adequacy with capital conservation buffer, amount	$ 165,106,000	$ 141,325,000
Required capital adequacy, ratio	10.50%	10.50%
Prompt corrective action provisions, amount	$ 157,244,000	$ 134,595,000
Prompt corrective action provisions, ratio	0.1000	0.1000
Tier 1 capital to average assets (leverage ratio):
Actual capital, amount	$ 176,593,000	$ 165,199,000
Actual capital, ratio	0.0783	0.1096
Required capital adequacy, amount	$ 90,220,000	$ 60,276,000
Required capital adequacy, ratio	0.0400	0.0400
Required capital adequacy with capital conservation buffer, amount	$ 90,220,000	$ 60,276,000
Required capital adequacy with capital conservation buffer, ratio	4.00%	4.00%
Prompt corrective action provisions, amount	$ 112,776,000	$ 75,345,000
Prompt corrective action provisions, ratio	0.0500	0.0500