Regulatory Matters - Schedule of Regulatory Capital Requirements (Detail) $ in Thousands	Jun. 30, 2026 USD ($)	Dec. 31, 2025 USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Actual, Total Capital (to risk- weighted assets)	$ 55,683	$ 55,405
Actual, Tier 1 Capital (to risk- weighted assets)	52,010	51,719
Actual, Tier 1 Capital (to average assets)	52,010	51,719
Actual, Common Equity Tier 1 (to risk-weighted assets)	$ 52,010	$ 51,719
Actual Ratio, Total Capital (to risk- weighted assets)	0.1596	0.156
Actual Ratio, Tier 1 Capital (to risk- weighted assets)	0.149	0.1456
Actual Ratio, Tier 1 Capital (to average assets)	0.0892	0.0841
Actual Ratio, Common Equity Tier 1 (to risk-weighted assets)	0.149	0.1456
Minimum Capital Requirement, Total Capital (to risk-weighted assets)	$ 27,919	$ 28,420
Minimum Capital Requirement, Tier 1 Capital (to risk-weighted assets)	20,939	21,315
Minimum Capital Requirement, Tier 1 Capital (to average assets)	23,322	24,605
Minimum Capital Requirement, Common Equity Tier 1 (to risk-weighted assets)	$ 15,704	$ 15,987
Minimum Capital Requirement Ratio, Total Capital (to risk-weighted assets)	0.08	0.08
Minimum Capital Requirement Ratio, Tier 1 Capital (to risk-weighted assets)	0.06	0.06
Minimum Capital Requirement Ratio, Tier 1 Capital (to average assets)	0.04	0.04
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)	$ 34,899	$ 35,526
Minimum Capital Required to be Well Capitalized, Tier 1 Capital (to risk-weighted assets)	27,919	28,420
Minimum Capital Required to be Well Capitalized, Tier 1 Capital (to average assets)	29,153	30,756
Minimum Capital Required to be Well Capitalized, Common Equity Tier 1 (to risk-weighted assets)	$ 22,684	$ 23,092
Minimum Capital Requirement Ratio, Total Capital (to risk-weighted assets)	0.10	0.10
Minimum Capital Requirement Ratio, Tier 1 Capital (to risk-weighted assets)	0.08	0.08
Minimum Capital Requirement Ratio, Tier 1 Capital (to average assets)	0.05	0.05
Minimum Capital Requirement Ratio, Common Equity Tier 1 (to risk-weighted assets)	0.065	0.065
Fully Phased In [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Minimum Capital Requirement, Total Capital (to risk-weighted assets)	$ 36,643	$ 37,302
Minimum Capital Requirement, Tier 1 Capital (to risk-weighted assets)	29,664	30,197
Minimum Capital Requirement, Tier 1 Capital (to average assets)	23,322	24,605
Minimum Capital Requirement, Common Equity Tier 1 (to risk-weighted assets)	$ 24,429	$ 24,868
Minimum Capital Requirement Ratio, Total Capital (to risk-weighted assets)	0.105	0.105
Minimum Capital Requirement Ratio, Tier 1 Capital (to risk-weighted assets)	0.085	0.085
Minimum Capital Requirement Ratio, Tier 1 Capital (to average assets)	0.04	0.04
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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Ratio of minimum Common Equity Tier 1 risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

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Amount of total capital as defined by regulatory framework.

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