Loans - Schedule of Accounts, Notes, Loans and Financing Receivable (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Total loans	$ 378,009	$ 374,991
Net deferred loan costs	1,814	1,650
Allowance for loan losses	(3,642)	(3,590)	$ (3,404)	$ (3,342)
Net loans	376,181	373,051
CRE [Member]
Total loans	76,397	72,057
Allowance for loan losses	(894)	(833)	(913)	(753)
MF [Member]
Total loans	8,900	8,998
Allowance for loan losses	(78)	(80)	(39)	(60)
C+I [Member]
Total loans	28,459	26,851
Allowance for loan losses	(218)	(194)	(206)	(267)
ADL [Member]
Total loans	17,423	21,365
Allowance for loan losses	(116)	(178)	(296)	(174)
RES [Member]
Total loans	235,273	234,199
Allowance for loan losses	(2,188)	(2,139)	(1,559)	(1,656)
HELOC [Member]
Total loans	6,569	6,947
Allowance for loan losses	(62)	(63)	(67)	(78)
CON [Member]
Total loans	4,988	4,574
Allowance for loan losses	$ (86)	$ (75)	$ (50)	$ (52)

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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