Loans - Schedule of Analysis of Past due Loans (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Loans, Notes and Certificates, and Loan Servicing Rights [Line Items]
Past Due / Current Loans	$ 359,876	$ 325,617
Loans, gross	361,947	325,992
Nonaccrual Loans	$ 769	$ 1,017
Total non-accrual loans to total loans	0.21%	0.31%
Total non-accrual loans to total assets	0.14%	0.19%
Commercial Real Estate [Member]
Loans, Notes and Certificates, and Loan Servicing Rights [Line Items]
Past Due / Current Loans	$ 209,126	$ 185,223
Loans, gross	210,858	185,223
Commercial Land Development [Member]
Loans, Notes and Certificates, and Loan Servicing Rights [Line Items]
Past Due / Current Loans	0	1,400
Loans, gross	0	1,400
Commercial Other [Member]
Loans, Notes and Certificates, and Loan Servicing Rights [Line Items]
Past Due / Current Loans	43,708	38,127
Loans, gross	43,708	38,160
Residential Real Estate First Mortgages [Member]
Loans, Notes and Certificates, and Loan Servicing Rights [Line Items]
Past Due / Current Loans	85,200	80,319
Loans, gross	85,444	80,661
Nonaccrual Loans	714	939
Residential Real Estate Construction [Member]
Loans, Notes and Certificates, and Loan Servicing Rights [Line Items]
Past Due / Current Loans	3,248	3,388
Loans, gross	3,248	3,388
Consumer Home Equity and Lines of Credit [Member]
Loans, Notes and Certificates, and Loan Servicing Rights [Line Items]
Past Due / Current Loans	18,497	17,032
Loans, gross	18,590	17,032
Nonaccrual Loans	55	78
Consumer Other [Member]
Loans, Notes and Certificates, and Loan Servicing Rights [Line Items]
Past Due / Current Loans	97	128
Loans, gross	99	128
Loans Past Due 30-89 Days [Member]
Loans, Notes and Certificates, and Loan Servicing Rights [Line Items]
Past Due / Current Loans	1,987	375
Loans Past Due 30-89 Days [Member] \| Commercial Real Estate [Member]
Loans, Notes and Certificates, and Loan Servicing Rights [Line Items]
Past Due / Current Loans	1,732	0
Loans Past Due 30-89 Days [Member] \| Commercial Other [Member]
Loans, Notes and Certificates, and Loan Servicing Rights [Line Items]
Past Due / Current Loans	0	33
Loans Past Due 30-89 Days [Member] \| Residential Real Estate First Mortgages [Member]
Loans, Notes and Certificates, and Loan Servicing Rights [Line Items]
Past Due / Current Loans	181	342
Loans Past Due 30-89 Days [Member] \| Consumer Home Equity and Lines of Credit [Member]
Loans, Notes and Certificates, and Loan Servicing Rights [Line Items]
Past Due / Current Loans	72	0
Loans Past Due 30-89 Days [Member] \| Consumer Other [Member]
Loans, Notes and Certificates, and Loan Servicing Rights [Line Items]
Past Due / Current Loans	2	0
Loans Past Due 90+ Days [Member]
Loans, Notes and Certificates, and Loan Servicing Rights [Line Items]
Past Due / Current Loans	84	0
Loans Past Due 90+ Days [Member] \| Residential Real Estate First Mortgages [Member]
Loans, Notes and Certificates, and Loan Servicing Rights [Line Items]
Past Due / Current Loans	63	0
Loans Past Due 90+ Days [Member] \| Consumer Home Equity and Lines of Credit [Member]
Loans, Notes and Certificates, and Loan Servicing Rights [Line Items]
Past Due / Current Loans	$ 21	$ 0

Loans and leases receivable, ratio of nonperforming loans to all assets.

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Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

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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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