Loans - Summary of Major Classifications of Loans (Detail) - USD ($) $ in Thousands		Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	[1]	$ 401,856		$ 397,714
Net deferred loan costs		818		854
Allowance for credit losses for loans		(3,871)	$ (3,679)	(3,734)	$ (3,643)	$ (3,693)	$ (3,203)
Total loans, net of deferred loan costs and allowance for credit losses		398,803		394,834
Commercial [Member] | Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross		237,645		231,893
Commercial [Member] | Other Commercial Loan [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross		46,078		47,898
Residential Real Estate [Member] | First Mortgage [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross		98,419		97,747
Residential Real Estate [Member] | Construction Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross		691		359
Consumer [Member] | Home Equity Lines Of Credit [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross		18,943		19,683
Consumer [Member] | Other Consumer Loan [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross		$ 80		$ 134

[1] Totals do not include accrued interest receivable, which was $1.1 million at both June 30, 2024 and December 31, 2023, and which is recorded separately on the Company’s Consolidated Balance Sheets.