Regulatory Matters - Schedule of Regulatory Capital Requirements (Detail) $ in Thousands	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Actual, Total Capital (to risk- weighted assets)	$ 53,699	$ 52,798
Actual, Tier 1 Capital (to risk- weighted assets)	50,004	49,151
Actual, Tier 1 Capital (to average assets)	50,004	49,151
Actual, Common Equity Tier 1 (to risk-weighted assets)	$ 50,004	$ 49,151
Actual Ratio, Total Capital (to risk- weighted assets)	0.1730	0.1787
Actual Ratio, Tier 1 Capital (to risk- weighted assets)	0.1611	0.1663
Actual Ratio, Tier 1 Capital (to average assets)	0.1011	0.0992
Actual Ratio, Common Equity Tier 1 (to risk-weighted assets)	0.1611	0.1663
Minimum Capital Requirement, Total Capital (to risk-weighted assets)	$ 24,836	$ 23,641
Minimum Capital Requirement, Tier 1 Capital (to risk-weighted assets)	18,627	17,731
Minimum Capital Requirement, Tier 1 Capital (to average assets)	19,779	19,811
Minimum Capital Requirement, Common Equity Tier 1 (to risk-weighted assets)	$ 13,970	$ 13,298
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%
Minimum Capital Required to be Well Capitalized, Total Capital (to risk-weighted assets)	$ 31,045	$ 29,546
Minimum Capital Required to be Well Capitalized, Tier 1 Capital (to risk-weighted assets)	24,836	23,644
Minimum Capital Required to be Well Capitalized, Tier 1 Capital (to average assets)	24,723	24,774
Minimum Capital Required to be Well Capitalized, Common Equity Tier 1 (to risk-weighted assets)	$ 20,179	$ 19,211
Minimum Capital Required to be Well Capitalized, Total Capital (to risk-weighted assets)	0.1000	0.1000
Minimum Capital Required to be Well Capitalized, Tier 1 Capital (to risk-weighted assets)	0.0800	0.0800
Minimum Capital Required to be Well Capitalized, Tier 1 Capital (to average assets)	0.0500	0.0500
Minimum Capital Required to be Well Capitalized, Common Equity Tier 1 (to risk-weighted assets)	0.0650	0.0650
Fully Phased In [Member]
Minimum Capital Requirement, Total Capital (to risk-weighted assets)	$ 32,598	$ 31,029
Minimum Capital Requirement, Tier 1 Capital (to risk-weighted assets)	26,388	25,119
Minimum Capital Requirement, Tier 1 Capital (to average assets)	19,779	19,811
Minimum Capital Requirement, Common Equity Tier 1 (to risk-weighted assets)	$ 21,732	$ 20,686
Minimum Capital Requirement Ratio, Total Capital (to risk-weighted assets)	0.1050	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%	7.00%

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

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