Income Taxes - Schedule of Reasons for Differences in Amount Computed by U.S. Federal Income Tax Rates (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Computed “expected” tax expense	$ 677	$ 222
State tax, net of federal tax benefit	118	(6)
BOLI income	(22)	(19)
Valuation allowance		(65)
Income on tax exempt securities	(178)	(182)
Other	6	26
Income tax expense (benefit)	$ 601	$ (24)
Computed “expected” tax expense	21.00%	21.00%
State tax, net of federal tax benefit	3.70%	(0.60%)
BOLI income	(0.70%)	(1.80%)
Valuation allowance		(6.20%)
Income on tax exempt securities	(5.50%)	(17.30%)
Other	0.20%	2.60%
Effective income tax rate	18.70%	(2.30%)