Fair Value Measurements - Summary of Carrying Values and Estimated Fair Values of Financial Instruments (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financial assets:
Available for sale securities	$ 67,940	$ 58,703
Loans	327,565	329,073
Accrued interest receivable	852	912
Cash value of life insurance	13,585	13,485
FHLB stock	3,032	3,032
Marketable securities	3,146	2,992
Financial liabilities:
Deposits	377,658	379,848
Advance payments by borrowers for taxes and insurance	6,097	2,737
FHLB advances	67,912	68,398
Fair Value, Inputs, Level 1 [Member]
Financial assets:
Cash and cash equivalents	83,481	92,526
Accrued interest receivable	852	912
Marketable securities	3,146	2,992
Financial liabilities:
Deposits	295,751	292,219
Advance payments by borrowers for taxes and insurance	6,097	2,737
Accrued interest payable	143	183
Fair Value, Inputs, Level 2 [Member]
Financial assets:
Available for sale securities	67,940	58,703
Loans held for sale	2,828	2,484
Fair Value, Inputs, Level 3 [Member]
Financial assets:
Loans	330,758	332,882
Rate lock commitments	189	354
Cash value of life insurance	13,585	13,485
FHLB stock	3,032	3,032
Financial liabilities:
Deposits	82,048	87,884
FHLB advances	69,667	70,561
Reported Value Measurement [Member]
Financial assets:
Cash and cash equivalents	83,481	92,526
Available for sale securities	67,940	58,703
Loans held for sale	2,828	2,484
Loans	327,565	329,073
Rate lock commitments	189	354
Accrued interest receivable	852	912
Cash value of life insurance	13,585	13,485
FHLB stock	3,032	3,032
Marketable securities	3,146	2,992
Financial liabilities:
Deposits	377,658	379,848
Advance payments by borrowers for taxes and insurance	6,097	2,737
FHLB advances	67,912	63,398
Accrued interest payable	$ 143	$ 183

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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 and equity securities categorized neither as held-to-maturity nor trading.

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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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