Equity and Regulatory Matters - Schedule of Banks Actual and Required Capital Amounts and Ratios (Detail) $ in Thousands	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Text Block [Abstract]
Leverage tier 1 capital actual amount	$ 62,191	$ 65,497
Common Equity Tier 1 risk based capital actual amount	62,191	65,497
Tier 1 risk based capital actual amount	62,191	65,497
Total risk based capital actual amount	$ 66,714	$ 68,700
Leverage tier 1 capital actual ratio	0.111	0.119
Common Equity Tier 1 risk based capital actual ratio	0.15	0.166
Tier 1 risk based capital actual ratio	0.15	0.166
Total risk based capital actual ratio	0.161	0.175
Leverage tier 1 capital for capital adequacy purposes amount	$ 22,440	$ 22,086
Common Equity Tier 1 risk based capital for capital adequacy purposes amount	18,624	17,711
Tier 1 risk based capital for capital adequacy purposes amount	24,831	23,615
Total risk based capital for capital adequacy purposes amount	$ 33,109	$ 31,486
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	$ 28,051	$ 27,608
Common Equity Tier 1 risk based capital to be well capitalized under prompt corrective action provisions amount	26,901	25,583
Tier 1 risk based capital to be well capitalized under prompt corrective action provisions amount	33,104	31,486
Total risk based capital to be well capitalized under prompt corrective action provisions amount	$ 41,386	$ 39,358
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//1943274/2147480696/942-505-50-1

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//1943274/2147480696/942-505-50-1B

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