Fair Value Measurements - Summary of Carrying Values and Estimated Fair Values of Financial Instruments (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Financial assets:
Securities available-for-sale	$ 66,875	$ 88,955
Loans	369,973	331,206
Accrued interest receivable	1,223	1,214
Cash surrender value of bank-owned life insurance	13,302	13,732
Federal Home Loan Bank stock	1,525	1,436
Financial liabilities:
Deposits	392,296	389,291
Advance payments made to borrowers for taxes and insurance	10,571	385
Federal Home Loan Bank advances	36,668	34,693
Fair Value, Inputs, Level 1 [Member]
Financial assets:
Cash and cash equivalents	8,956	12,497
Accrued interest receivable	1,223	1,214
Financial liabilities:
Deposits	204,772	203,048
Advance payments made to borrowers for taxes and insurance	10,571	385
Accrued interest payable	343	340
Fair Value, Inputs, Level 2 [Member]
Financial assets:
Securities available-for-sale	66,875	88,955
Loans held-for-sale	901	217
Fair Value, Inputs, Level 3 [Member]
Financial assets:
Loans	363,923	328,526
Cash surrender value of bank-owned life insurance	13,302	13,732
Federal Home Loan Bank stock	1,525	1,436
Financial liabilities:
Deposits	185,493	185,758
Federal Home Loan Bank advances	36,119	34,229
Reported Value Measurement [Member]
Financial assets:
Cash and cash equivalents	8,956	12,497
Securities available-for-sale	66,875	88,955
Loans held-for-sale	901	217
Loans	369,973	331,206
Accrued interest receivable	1,223	1,214
Cash surrender value of bank-owned life insurance	13,302	13,732
Federal Home Loan Bank stock	1,525	1,436
Financial liabilities:
Deposits	392,296	389,291
Advance payments made to borrowers for taxes and insurance	10,571	385
Federal Home Loan Bank advances	36,668	34,693
Accrued interest payable	$ 343	$ 340

Accrued interest payable.

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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 allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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