Fair Value Measurements - Summary of Carrying Values and Estimated Fair Values of Financial Instruments (Detail) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Financial assets:
Available for sale securities	$ 104,641	$ 114,492
Loans, net	382,682	359,574
Accrued interest receivable	1,349	1,257
Cash value of life insurance	13,919	14,316
FHLB Stock	4,787	3,429
Marketable securities	3,286	2,924
Financial liabilities:
Deposits	386,973	387,721
Advance payments by borrowers for taxes and insurance	10,264	1,029
FHLB advances	78,499	71,464
Fair Value, Inputs, Level 1 [Member]
Financial assets:
Cash and cash equivalents	26,603	28,344
Accrued interest receivable	1,349	1,257
Marketable securities	3,286	2,924
Financial liabilities:
Deposits	237,772	308,162
Advance payments by borrowers for taxes and insurance	10,264	1,029
Accrued interest payable	1,099	291
Fair Value, Inputs, Level 2 [Member]
Financial assets:
Available for sale securities	104,641	114,492
Loans held for sale	410	125
Fair Value, Inputs, Level 3 [Member]
Financial assets:
Loans, net	353,717	335,987
Rate lock commitments	6	6
Cash value of life insurance	13,919	14,316
FHLB Stock	4,787	3,429
Financial liabilities:
Deposits	147,476	78,418
FHLB advances	74,667	69,633
Reported Value Measurement [Member]
Financial assets:
Cash and cash equivalents	26,603	28,344
Available for sale securities	104,641	114,492
Loans held for sale	410	125
Loans, net	382,682	359,574
Rate lock commitments	6	6
Accrued interest receivable	1,349	1,257
Cash value of life insurance	13,919	14,316
FHLB Stock	4,787	3,429
Marketable securities	3,286	2,924
Financial liabilities:
Deposits	386,973	387,721
Advance payments by borrowers for taxes and insurance	10,264	1,029
FHLB advances	78,499	71,464
Accrued interest payable	$ 1,099	$ 291

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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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