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, 2021	Dec. 31, 2020
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Federal income taxes at statutory rate, Amount	$ 5	$ 641
Increase in cash value of life insurance, Amount	(85)	(84)
Change in valuation allowance, Amount		934
Other net, Amount	16	245
Total income tax expense (benefit), Amount	$ (64)	$ 1,736
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	(357.00%)	(2.75%)
Change in valuation allowance, Percentage	0.00%	30.60%
Other net, Percentage	67.20%	8.03%
Total income tax expense (benefit), Percentage	(268.80%)	56.88%