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Regulatory Matters - Schedule of Regulatory Capital Requirements (Detail) $ in Thousands | Sep. 30, 2025 USD ($) | Dec. 31, 2024 USD ($)
--- | --- | ---
Actual, Total Capital (to risk- weighted assets) | $ 55,637 | $ 55,506
Actual, Tier 1 Capital (to risk- weighted assets) | 51,900 | 51,820
Actual, Tier 1 Capital (to average assets) | 51,900 | 51,820
Actual, Common Equity Tier 1 (to risk-weighted assets) | $ 51,900 | $ 51,820
Actual Ratio, Total Capital (to risk- weighted assets) | 0.1553 | 0.1555
Actual Ratio, Tier 1 Capital (to risk- weighted assets) | 0.1448 | 0.1452
Actual Ratio, Tier 1 Capital (to average assets) | 0.0844 | 0.0869
Actual Ratio, Common Equity Tier 1 (to risk-weighted assets) | 0.1448 | 0.1452
Minimum Capital Requirement, Total Capital (to risk-weighted assets) | $ 28,666 | $ 28,555
Minimum Capital Requirement, Tier 1 Capital (to risk-weighted assets) | 21,500 | 21,417
Minimum Capital Requirement, Tier 1 Capital (to average assets) | 24,607 | 23,848
Minimum Capital Requirement, Common Equity Tier 1 (to risk-weighted assets) | $ 16,125 | $ 16,062
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) | $ 35,833 | $ 35,694
Minimum Capital Required to be Well Capitalized, Tier 1 Capital (to risk-weighted assets) | 28,666 | 28,555
Minimum Capital Required to be Well Capitalized, Tier 1 Capital (to average assets) | 30,759 | 29,809
Minimum Capital Required to be Well Capitalized, Common Equity Tier 1 (to risk-weighted assets) | $ 23,291 | $ 23,201
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 [Member] |  |
Minimum Capital Requirement, Total Capital (to risk-weighted assets) | $ 37,624 | $ 37,479
Minimum Capital Requirement, Tier 1 Capital (to risk-weighted assets) | 30,458 | 30,340
Minimum Capital Requirement, Tier 1 Capital (to average assets) | 24,607 | 23,848
Minimum Capital Requirement, Common Equity Tier 1 (to risk-weighted assets) | $ 25,083 | $ 24,986
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%

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