Fair Value - Summary of Carrying Values and Estimated Fair Values of Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Financial assets:
Available for sale securities	$ 114,492	$ 112,440
Loans	359,574	323,789
Accrued interest receivable	1,257	948
Cash value of life insurance	14,316	13,892
Federal Home Loan Bank (FHLB) stock, at cost	3,429	3,032
Marketable securities	2,924	3,544
Financial liabilities:
Deposits	387,721	384,501
Advance payments by borrowers for taxes and insurance	1,029	1,860
FHLB advances	71,464	55,442
Fair Value, Inputs, Level 1 [Member]
Financial assets:
Cash and cash equivalents	28,344	66,803
Accrued interest receivable	1,257	948
Marketable securities	2,924	3,544
Financial liabilities:
Deposits	308,162	303,908
Advance payments by borrowers for taxes and insurance	1,029	1,860
Accrued interest payable	291	109
Fair Value, Inputs, Level 2 [Member]
Financial assets:
Available for sale securities	114,492	112,440
Loans held for sale	125	1,183
Fair Value, Inputs, Level 3 [Member]
Financial assets:
Loans	335,987	323,182
Rate lock commitments	6	30
Cash value of life insurance	14,316	13,892
Federal Home Loan Bank (FHLB) stock, at cost	3,429	3,032
Financial liabilities:
Deposits	78,418	80,473
FHLB advances	69,633	55,981
Reported Value Measurement [Member]
Financial assets:
Cash and cash equivalents	28,344	66,803
Available for sale securities	114,492	112,440
Loans held for sale	125	1,183
Loans	359,574	323,789
Rate lock commitments	6	30
Accrued interest receivable	1,257	948
Cash value of life insurance	14,316	13,892
Federal Home Loan Bank (FHLB) stock, at cost	3,429	3,032
Marketable securities	2,924	3,544
Financial liabilities:
Deposits	387,721	384,501
Advance payments by borrowers for taxes and insurance	1,029	1,860
FHLB advances	71,464	55,442
Accrued interest payable	$ 291	$ 109

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Rate lock commitments

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Carrying amount of accumulated prepayments received by financial institutions from borrowers for taxes (for example, property taxes) and insurance (for example, property and catastrophe) which will periodically be remitted to the appropriate governmental agency or vendor on behalf of the borrower.

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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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, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

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Amount of investment in marketable security.

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