Fair Value - Summary of Carrying Values and Estimated Fair Values of Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financial assets:
Available for sale securities	$ 58,703	$ 71,375
Loans	329,073	310,674
Accrued interest receivable	912	963
Cash value of life insurance	13,485	13,085
FHLB stock	3,032	913
Marketable securities	2,992	2,553
Financial liabilities:
Deposits	379,848	344,596
Advance payments by borrowers for taxes and insurance	2,737	1,681
FHLB advances	68,398	17,623
Fair Value, Inputs, Level 1 [Member]
Financial assets:
Cash and cash equivalents	92,526	11,707
Accrued interest receivable	912	963
Marketable securities	2,992	2,553
Financial liabilities:
Deposits	292,219	202,180
Advance payments by borrowers for taxes and insurance	2,737	1,681
Accrued interest payable	183	385
Fair Value, Inputs, Level 2 [Member]
Financial assets:
Available for sale securities	58,703	71,375
Loans held for sale	2,484	685
Fair Value, Inputs, Level 3 [Member]
Financial assets:
Loans	332,882	310,993
Rate lock commitments	354
Cash value of life insurance	13,485	13,085
FHLB stock	3,032	913
Financial liabilities:
Deposits	87,884	142,708
FHLB advances	70,561	17,976
Reported Value Measurement [Member]
Financial assets:
Cash and cash equivalents	92,526	11,707
Available for sale securities	58,703	71,375
Loans held for sale	2,484	685
Loans	329,073	310,674
Rate lock commitments	354
Accrued interest receivable	912	963
Cash value of life insurance	13,485	13,085
FHLB stock	3,032	913
Marketable securities	2,992	2,553
Financial liabilities:
Deposits	379,848	344,596
Advance payments by borrowers for taxes and insurance	2,737	1,681
FHLB advances	63,398	17,623
Accrued interest payable	$ 183	$ 385

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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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