Regulatory Matters - Schedule of Regulatory Capital Requirements (Detail) $ in Thousands	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Actual, Total Capital (to risk- weighted assets)	$ 65,881	$ 52,475
Actual, Tier 1 Capital (to risk- weighted assets)	62,191	48,821
Actual, Tier 1 Capital (to average assets)	62,191	48,821
Actual, Common Equity Tier 1 (to risk-weighted assets)	$ 62,191	$ 48,821
Actual Ratio, Total Capital (to risk- weighted assets)	0.1869	0.1553
Actual Ratio, Tier 1 Capital (to risk- weighted assets)	0.1764	0.1445
Actual Ratio, Tier 1 Capital (to average assets)	0.1137	0.0920
Actual Ratio, Common Equity Tier 1 (to risk-weighted assets)	0.1764	0.1445
Minimum Capital Requirement, Total Capital (to risk-weighted assets)	$ 28,203	$ 27,028
Minimum Capital Requirement, Tier 1 Capital (to risk-weighted assets)	21,153	20,271
Minimum Capital Requirement, Tier 1 Capital (to average assets)	21,869	21,224
Minimum Capital Requirement, Common Equity Tier 1 (to risk-weighted assets)	$ 15,865	$ 15,203
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)	$ 35,254	$ 33,785
Minimum Capital Required to be Well Capitalized, Tier 1 Capital (to risk-weighted assets)	28,205	27,028
Minimum Capital Required to be Well Capitalized, Tier 1 Capital (to average assets)	27,337	26,530
Minimum Capital Required to be Well Capitalized, Common Equity Tier 1 (to risk-weighted assets)	$ 22,916	$ 21,960
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)	$ 37,016	$ 35,474
Minimum Capital Requirement, Tier 1 Capital (to risk-weighted assets)	29,967	28,717
Minimum Capital Requirement, Tier 1 Capital (to average assets)	21,869	21,224
Minimum Capital Requirement, Common Equity Tier 1 (to risk-weighted assets)	$ 24,679	$ 23,649
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//1943274/2147480696/942-505-50-1

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