Equity and Regulatory Matters - Schedule of Banks Actual and Required Capital Amounts and Ratios (Detail) $ in Thousands	Sep. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
Text Block [Abstract]
Leverage tier 1 capital actual amount	$ 63,150	$ 63,101
Common Equity Tier 1 risk based capital actual amount	63,150	63,101
Tier 1 risk based capital actual amount	63,150	63,101
Total risk based capital actual amount	$ 68,096	$ 67,710
Leverage tier 1 capital actual ratio	0.112	0.112
Common Equity Tier 1 risk based capital actual ratio	0.149	0.151
Tier 1 risk based capital actual ratio	0.149	0.151
Total risk based capital actual ratio	0.16	0.162
Leverage tier 1 capital for capital adequacy purposes amount	$ 22,551	$ 22,574
Common Equity Tier 1 risk based capital for capital adequacy purposes amount	19,109	18,751
Tier 1 risk based capital for capital adequacy purposes amount	25,479	25,002
Total risk based capital for capital adequacy purposes amount	$ 33,972	$ 33,336
Leverage tier 1 capital for capital adequacy purposes ratio	4.00%	4.00%
Common Equity Tier 1 risk based capital for capital adequacy purposes ratio	0.045	0.045
Tier 1 risk based capital for capital adequacy purposes ratio	0.06	0.06
Total risk based capital for capital adequacy purposes ratio	0.08	0.08
Leverage tier 1 capital to be well capitalized under prompt corrective action provisions amount	$ 28,189	$ 28,217
Common Equity Tier 1 risk based capital to be well capitalized under prompt corrective action provisions amount	27,602	27,085
Tier 1 risk based capital to be well capitalized under prompt corrective action provisions amount	33,972	33,336
Total risk based capital to be well capitalized under prompt corrective action provisions amount	$ 42,465	$ 41,670
Leverage tier 1 capital to be well capitalized under prompt corrective action provisions ratio	5.00%	5.00%
Common Equity Tier 1 risk based capital to be well capitalized under prompt corrective action provisions ratio	0.065	0.065
Tier 1 risk based capital to be well capitalized under prompt corrective action provisions ratio	0.08	0.08
Total risk based capital to be well capitalized under prompt corrective action provisions ratio	0.10	0.10

Common Equity Tier One Capital Required To Be Well Capitalized To Risk Weighted Assets

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Common Equity Tier One Risk Based Capital Required For Capital Adequacy

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The minimum Common Tier One Capital Ratio (Common Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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Amount of total capital as defined by regulatory framework.

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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
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1B

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