Loans - Summary of Activity in Allowance for Loan and Lease Losses (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Loans and Leases Receivable Disclosure [Line Items]
Beginning balance	$ 2,703	$ 2,000
Provision (credit) for loan losses	30	500
Loans charged-off	(19)	(68)
Recoveries of loans previously charged off	144	271
Ending balance	2,858	2,703
Commercial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Beginning balance	1,609	1,235
Provision (credit) for loan losses	30	360
Loans charged-off	0
Recoveries of loans previously charged off	18	14
Ending balance	1,657	1,609
Residential [Member]
Loans and Leases Receivable Disclosure [Line Items]
Beginning balance	745	573
Provision (credit) for loan losses	0	100
Loans charged-off	0	(60)
Recoveries of loans previously charged off	0	132
Ending balance	745	745
Consumer [Member]
Loans and Leases Receivable Disclosure [Line Items]
Beginning balance	349	192
Provision (credit) for loan losses	0	40
Loans charged-off	(19)	(8)
Recoveries of loans previously charged off	126	125
Ending balance	$ 456	$ 349