Regulatory Matters - Schedule of Regulatory Capital Requirements (Detail) $ in Thousands	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Actual, Total Capital (to risk- weighted assets)	$ 52,475	$ 52,798
Actual, Tier 1 Capital (to risk- weighted assets)	48,821	49,151
Actual, Tier 1 Capital (to average assets)	48,821	49,151
Actual, Common Equity Tier 1 (to risk-weighted assets)	$ 48,821	$ 49,151
Actual Ratio, Total Capital (to risk- weighted assets)	0.1553	0.1787
Actual Ratio, Tier 1 Capital (to risk- weighted assets)	0.1445	0.1663
Actual Ratio, Tier 1 Capital (to average assets)	0.0920	0.0992
Actual Ratio, Common Equity Tier 1 (to risk-weighted assets)	0.1445	0.1663
Minimum Capital Requirement, Total Capital (to risk-weighted assets)	$ 27,028	$ 23,641
Minimum Capital Requirement, Tier 1 Capital (to risk-weighted assets)	20,271	17,731
Minimum Capital Requirement, Tier 1 Capital (to average assets)	21,224	19,811
Minimum Capital Requirement, Common Equity Tier 1 (to risk-weighted assets)	$ 15,203	$ 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)	$ 33,785	$ 29,546
Minimum Capital Required to be Well Capitalized, Tier 1 Capital (to risk-weighted assets)	27,028	23,644
Minimum Capital Required to be Well Capitalized, Tier 1 Capital (to average assets)	26,530	24,774
Minimum Capital Required to be Well Capitalized, Common Equity Tier 1 (to risk-weighted assets)	$ 21,960	$ 19,211
Minimum Capital Requirement Ratio, Total Capital (to risk-weighted assets)	0.1000	0.1000
Minimum Capital Requirement Ratio, Tier 1 Capital (to risk-weighted assets)	0.0800	0.0800
Minimum Capital Requirement Ratio, Tier 1 Capital (to average assets)	0.0500	0.0500
Minimum Capital Requirement Ratio, Common Equity Tier 1 (to risk-weighted assets)	0.0650	0.0650
Fully Phased In
Minimum Capital Requirement, Total Capital (to risk-weighted assets)	$ 35,474	$ 31,029
Minimum Capital Requirement, Tier 1 Capital (to risk-weighted assets)	28,717	25,119
Minimum Capital Requirement, Tier 1 Capital (to average assets)	21,224	19,811
Minimum Capital Requirement, Common Equity Tier 1 (to risk-weighted assets)	$ 23,649	$ 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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