Stockholders' Equity - Summary of capital comparison with minimum requirements (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Jan. 01, 2016
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Annual increase in capital (to risk weighted assets) for capital adequacy purposes ratio	0.625%
Common Equity Tier I Capital (to Risk Weighted Assets) Actual Amount	$ 37,592	$ 36,442
Common Equity Tier I Capital (to Risk Weighted Assets) Actual Ratio	15.32%	13.09%
Common Equity Tier I Capital (to Risk Weighted Assets) For Capital Adequacy Purposes Actual Amount	$ 11,044	$ 12,532
Common Equity Tier I Capital (to Risk Weighted Assets) For Capital Adequacy Purposes Actual Ratio	4.50%	4.50%
Common Equity Tier I Capital (to Risk Weighted Assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Actual Amount	$ 15,952	$ 18,101
Common Equity Tier I Capital (to Risk Weighted Assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Actual Ratio	6.50%	6.50%
Total Capital (to Risk Weighted Assets) Actual Amount	$ 39,329	$ 37,951
Total Capital (to Risk Weighted Assets) Actual Ratio	16.03	13.63
Total Capital (to Risk Weighted Assets) For Capital Adequacy Purposes Amount	$ 19,634	$ 22,278
Total Capital (to Risk Weighted Assets) For Capital Adequacy Purposes Ratio	8.00	8.00	0.625
Total Capital (to Risk Weighted Assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 24,542	$ 27,848
Total Capital (to Risk Weighted Assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	10.00	10.00
Tier I Capital (to Risk Weighted Assets) Actual Amount	$ 37,592	$ 36,442
Tier I Capital (to Risk Weighted Assets) Actual Ratio	15.32	13.09
Tier I Capital (to Risk Weighted Assets) For Capital Adequacy Purposes Amount	$ 14,725	$ 16,709
Tier I Capital (to Risk Weighted Assets) For Capital Adequacy Purposes Ratio	6.00	6.00
Tier I Capital (to Risk Weighted Assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 19,634	$ 22,278
Tier I Capital (to Risk Weighted Assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	8.00	8.00
Tier I Capital (to Average Assets) Actual Amount	$ 37,592	$ 36,442
Tier I Capital (to Average Assets) Actual Ratio	8.40	9.12
Tier I Capital (to Average Assets) For Capital Adequacy Purposes Amount	$ 17,910	$ 15,980
Tier I Capital (to Average Assets) For Capital Adequacy Purposes Ratio	4.00	4.00
Tier I Capital (to Average Assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 22,388	$ 19,975
Tier I Capital (to Average Assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	5.00	5.00
Minimum
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier I Capital (to Risk Weighted Assets) For Capital Adequacy Purposes Actual Ratio	4.50%
Total Capital (to Risk Weighted Assets) Actual Ratio	8.0
Tier I Capital (to Risk Weighted Assets) Actual Ratio	4.0
Tier I Capital (to Average Assets) Actual Ratio	4.0
Maximum
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Capital (to Risk Weighted Assets) For Capital Adequacy Purposes Ratio	2.5
Tier I Capital (to Risk Weighted Assets) Actual Ratio	6.0