Loans and Allowance for Credit Losses on Loans - Schedule of Accounts, Notes, Loans and Financing Receivable (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021
Total loans	$ 414,512		$ 400,056
Net deferred loan costs	2,547		2,449
Allowance for credit losses on loans	(3,319)	$ (3,287)	(3,581)	$ (3,644)	$ (3,642)	$ (3,590)
Net loans	413,740		398,924
CRE [Member]
Total loans	88,051		80,506
Allowance for credit losses on loans	(806)	(725)	(942)	(1,019)	(894)	(833)
MF [Member]
Total loans	7,787		8,185
Allowance for credit losses on loans	(49)	(49)	(54)	(57)	(78)	(80)
C+I [Member]
Total loans	24,168		24,059
Allowance for credit losses on loans	(277)	(281)	(184)	(208)	(218)	(194)
ADL [Member]
Total loans	14,999		18,490
Allowance for credit losses on loans	(70)	(96)	(138)	(110)	(116)	(178)
RES [Member]
Total loans	259,562		251,466
Allowance for credit losses on loans	(1,910)	(1,904)	(2,048)	(2,025)	(2,188)	(2,139)
HELOC [Member]
Total loans	12,121		10,161
Allowance for credit losses on loans	(85)	(88)	(81)	(87)	(62)	(63)
CON [Member]
Total loans	7,824		7,189
Allowance for credit losses on loans	$ (109)	$ (119)	$ (100)	$ (111)	$ (86)	$ (75)

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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