Income Taxes - Summary of the Sources of Differences Between Income Taxes At the Federal Statutory Rate and the Provision (Credit) for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Federal income taxes at statutory rate, Amount	$ (67)	$ 5
Increase in cash value of life insurance, Amount	(89)	(85)
Other net, Amount	(15)	16
Total income tax expense (benefit), Amount	$ (171)	$ (64)
Reconciliation of statutory to effective rates: Percentage
Federal income taxes at statutory rate, Percentage	21.00%	21.00%
Increase in cash value of life insurance, Percentage	27.90%	(357.00%)
Other net, Percentage	4.70%	67.20%
Total income tax expense (benefit), Percentage	53.60%	(268.80%)