Fair Value Measurements and Disclosures - Summary of Fair Values of Company's Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financial Assets
Cash and cash equivalents	$ 39,847	$ 59,618
Interest-bearing deposits in banks	449	939
Investment securities available for sale	257,321	260,131
Investment securities held to maturity	7,149	10,872
Mortgage loans held for sale	6,990	2,086
Loans, net	1,696,493	1,633,406
Cash surrender value of BOLI	39,466	29,560
Financial Liabilities
Deposits	1,820,975	1,773,217
Other borrowings	5,539	5,539
Long-term FHLB advances	40,620	58,698
Fair Value
Financial Assets
Cash and cash equivalents	39,847	59,618
Interest-bearing deposits in banks	449	939
Investment securities available for sale	257,321	260,131
Investment securities held to maturity	7,194	10,841
Mortgage loans held for sale	6,990	2,086
Loans, net	1,690,308	1,623,920
Cash surrender value of BOLI	39,466	29,560
Financial Liabilities
Deposits	1,821,868	1,769,087
Other borrowings	5,895	5,542
Long-term FHLB advances	40,580	57,527
Level 1 \| Fair Value
Financial Assets
Cash and cash equivalents	39,847	59,618
Interest-bearing deposits in banks	449	939
Investment securities available for sale	0	0
Investment securities held to maturity	0	0
Mortgage loans held for sale	0	0
Loans, net	0	0
Cash surrender value of BOLI	39,466	29,560
Financial Liabilities
Deposits	0	0
Other borrowings	0	0
Long-term FHLB advances	0	0
Level 2 \| Fair Value
Financial Assets
Cash and cash equivalents	0	0
Interest-bearing deposits in banks	0	0
Investment securities available for sale	257,321	260,131
Investment securities held to maturity	7,194	10,841
Mortgage loans held for sale	6,990	2,086
Loans, net	1,682,943	1,615,197
Cash surrender value of BOLI	0	0
Financial Liabilities
Deposits	1,821,868	1,769,087
Other borrowings	5,895	5,542
Long-term FHLB advances	40,580	57,527
Level 3 \| Fair Value
Financial Assets
Cash and cash equivalents	0	0
Interest-bearing deposits in banks	0	0
Investment securities available for sale	0	0
Investment securities held to maturity	0	0
Mortgage loans held for sale	0	0
Loans, net	7,365	8,723
Cash surrender value of BOLI	0	0
Financial Liabilities
Deposits	0	0
Other borrowings	0	0
Long-term FHLB advances	$ 0	$ 0

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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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The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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Amount of investment in debt security measured at amortized cost (held-to-maturity).

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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums over and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans and leases covered under loss sharing agreements.

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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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