Regulatory Matters - Schedule of Actual and Required Capital Amounts and Ratios of the Bank (Detail) - USD ($)	Mar. 31, 2023	Dec. 31, 2022
Schedule Of Compliance With Regulatory Capital Requirements Under Banking Regulations [Abstract]
Common Equity Tier 1 Capital to Risk-Weighted Assets, Actual Amount	$ 67,355	$ 67,153
Total Capital to Risk - Weighted Assets, Actual Amount	71,257	71,094
Tier 1 Capital to Risk - Weighted Assets, Actual Amount	67,355	67,153
Tier I Capital to Average Assets, Actual Amount	$ 67,355	$ 67,153
Common Equity Tier 1 Capital to Risk-Weighted Assets, Actual Ratio	21.64%	21.32%
Total Capital to Risk - Weighted Assets, Actual Ratio	22.89%	22.57%
Tier 1 Capital to Risk - Weighted Assets, Actual Ratio	21.64%	21.32%
Tier I Capital to Average Assets, Actual Ratio	15.59%	16.22%
Common Equity Tier 1 Capital to Risk-Weighted Assets, For Capital Adequacy Purposes Amount	$ 14,008	$ 14,172
Total Capital to Risk - Weighted Assets, For Capital Adequacy Purposes Amount	24,904	25,194
Tier 1 Capital to Risk - Weighted Assets, For Capital Adequacy Purposes Amount	18,678	18,895
Tier I Capital to Average Assets, For Capital Adequacy Purposes Amount	$ 17,277	$ 16,558
Common Equity Tier 1 Capital to Risk-Weighted Assets, For Capital Adequacy Purposes Ratio	4.50%	4.50%
Total Capital to Risk - Weighted Assets, For Capital Adequacy Purposes Ratio	8.00%	8.00%
Tier 1 Capital to Risk - Weighted Assets, For Capital Adequacy Purposes Ratio	6.00%	6.00%
Tier I Capital to Average Assets, For Capital Adequacy Purposes Ratio	4.00%	4.00%
Common Equity Tier 1 Capital to Risk-Weighted Assets, To Be Well Capitalized Under prompt Corrective Action Provisions Amount	$ 20,234	$ 20,470
Total Capital to Risk - Weighted Assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	31,130	31,492
Tier 1 Capital to Risk - Weighted Assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	24,904	25,194
Tier I Capital to Average Assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 21,596	$ 20,697
Common Equity Tier 1 Capital to Risk-Weighted Assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	6.50%	6.50%
Total Capital to Risk - Weighted Assets, To Be Well Capitalization Under Prompt Corrective Action Provisions Ratio	10.00%	10.00%
Tier 1 Capital to Risk - Weighted Assets, To Be Well Capitalization Under Prompt Corrective Action Provisions Ratio	8.00%	8.00%
Tier I Capital to Average Assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	5.00%	5.00%

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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Common tier one risk based capital required for capital adequacy to risk weighted assets.

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Schedule of compliance with regulatory capital requirements under banking regulations.

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Amount of total capital as defined by regulatory framework.

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Amount of minimum total risk-based capital required for capital adequacy as defined by regulatory framework.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
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