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 of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes 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, 2021	Dec. 31, 2020	Dec. 31, 2019
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	$ 325,992	$ 331,598
Net deferred loan costs	655	178
Allowance for loan losses	(2,858)	(2,703)	$ (2,000)
Loans, net	323,789	329,073
Commercial [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	185,223	189,291
Commercial [Member] \| Land [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	1,400	1,492
Commercial [Member] \| Other Commercial Loan [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	38,160	46,184
Residential Real Estate [Member] \| First Mortgage [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	80,661	68,968
Residential Real Estate [Member] \| Construction Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	3,388	2,954
Consumer [Member] \| Other Consumer Loan [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	128	361
Consumer [Member] \| Home Equity Lines Of Credit [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	$ 17,032	$ 22,348