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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Loans - Summary of Major Classifications of Loans (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	$ 397,714	$ 361,947
Net deferred loan costs	854	830
Allowance for credit losses for loans	(3,734)	(3,203)	$ (2,858)
Total loans, net of deferred loan costs and allowance for credit losses	394,834	359,574
Commercial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross		0
Commercial [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	231,893	210,858
Commercial [Member] \| Other Commercial Loan [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	47,898	43,708
Residential Real Estate [Member] \| First Mortgage [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	97,747	85,444
Residential Real Estate [Member] \| Construction Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	359	3,248
Consumer [Member] \| Home Equity Lines Of Credit [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	19,683	18,590
Consumer [Member] \| Other Consumer Loan [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	$ 134	$ 99