Regulatory Matters - Schedule of Regulatory Capital Requirements (Detail) $ in Thousands	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Actual, Total Capital (to risk- weighted assets)	$ 52,798	$ 50,612
Actual, Tier 1 Capital (to risk- weighted assets)	49,151	47,222
Actual, Tier 1 Capital (to average assets)	49,151	47,222
Actual, Common Equity Tier 1 (to risk-weighted assets)	$ 49,151	$ 47,222
Actual Ratio, Total Capital (to risk- weighted assets)	0.1787	0.1792
Actual Ratio, Tier 1 Capital (to risk- weighted assets)	0.1663	0.1672
Actual Ratio, Tier 1 Capital (to average assets)	0.0992	0.1059
Actual Ratio, Common Equity Tier 1 (to risk-weighted assets)	0.1663	0.1672
Minimum Capital Requirement, Total Capital (to risk-weighted assets)	$ 23,641	$ 22,593
Minimum Capital Requirement, Tier 1 Capital (to risk-weighted assets)	17,731	16,945
Minimum Capital Requirement, Tier 1 Capital (to average assets)	19,811	17,836
Minimum Capital Requirement, Common Equity Tier 1 (to risk-weighted assets)	$ 13,298	$ 12,709
Minimum Capital Requirement Ratio, Total Capital (to risk-weighted assets)	0.0800	0.0800
Minimum Capital Requirement Ratio, Tier 1 Capital (to risk-weighted assets)	0.0600	0.0600
Minimum Capital Requirement Ratio, Tier 1 Capital (to average assets)	0.0400	0.0400
Minimum Capital Requirement Ratio, Common Equity Tier 1 (to risk-weighted assets)	4.50%	4.50%
Fully Phased In
Minimum Capital Requirement, Total Capital (to risk-weighted assets)	$ 31,029
Minimum Capital Requirement, Tier 1 Capital (to risk-weighted assets)	25,119	$ 24,005
Minimum Capital Requirement, Tier 1 Capital (to average assets)	19,811	$ 17,836
Minimum Capital Requirement, Common Equity Tier 1 (to risk-weighted assets)	$ 20,686
Minimum Capital Requirement Ratio, Total Capital (to risk-weighted assets)	0.1050
Minimum Capital Requirement Ratio, Tier 1 Capital (to risk-weighted assets)	0.0850	0.0850
Minimum Capital Requirement Ratio, Tier 1 Capital (to average assets)	0.0400	0.0400
Minimum Capital Requirement Ratio, Common Equity Tier 1 (to risk-weighted assets)	7.00%
Minimum To Be Well Capitalized Under Prompt Corrective, Total Capital (to risk-weighted assets)		$ 29,653
Minimum To Be Well Capitalized Under Prompt Corrective, Common Equity Tier 1 (to risk-weighted assets)		$ 19,769
Minimum To Be Well Capitalized Under Prompt Corrective Ratio, Total Capital (to risk-weighted assets)		0.1050
Minimum To Be Well Capitalized Under Prompt Corrective Ratio, Common Equity Tier 1 (to risk-weighted assets)		7.00%

Common Equity Tier One Capital Required For Adequacy To Risk based Assets.

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Amount of Tier 1 leverage capital as defined by regulatory framework.

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