Regulatory Matters - Schedule of Regulatory Capital Requirements (Detail) $ in Thousands	Sep. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
Actual, Total Capital (to risk- weighted assets)	$ 57,150	$ 55,701
Actual, Tier 1 Capital (to risk- weighted assets)	53,414	51,878
Actual, Tier 1 Capital (to average assets)	53,414	51,878
Actual, Common Equity Tier 1 (to risk-weighted assets)	$ 53,414	$ 51,878
Actual Ratio, Total Capital (to risk- weighted assets)	0.1566	0.1532
Actual Ratio, Tier 1 Capital (to risk- weighted assets)	0.1464	0.1427
Actual Ratio, Tier 1 Capital (to average assets)	0.0905	0.0919
Actual Ratio, Common Equity Tier 1 (to risk-weighted assets)	0.1464	0.1427
Minimum Capital Requirement, Total Capital (to risk-weighted assets)	$ 29,192	$ 29,090
Minimum Capital Requirement, Tier 1 Capital (to risk-weighted assets)	21,894	21,818
Minimum Capital Requirement, Tier 1 Capital (to average assets)	23,617	22,592
Minimum Capital Requirement, Common Equity Tier 1 (to risk-weighted assets)	$ 16,420	$ 16,363
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)	$ 36,490	$ 36,363
Minimum Capital Required to be Well Capitalized, Tier 1 Capital (to risk-weighted assets)	29,192	29,090
Minimum Capital Required to be Well Capitalized, Tier 1 Capital (to average assets)	29,522	28,240
Minimum Capital Required to be Well Capitalized, Common Equity Tier 1 (to risk-weighted assets)	$ 23,718	$ 23,636
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)	$ 38,314	$ 38,181
Minimum Capital Requirement, Tier 1 Capital (to risk-weighted assets)	31,016	30,908
Minimum Capital Requirement, Tier 1 Capital (to average assets)	23,617	22,592
Minimum Capital Requirement, Common Equity Tier 1 (to risk-weighted assets)	$ 25,543	$ 25,454
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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
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