Fair Value of Financial Instruments - Summary of Estimated Fair Values of Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Assets
Cash and due from banks	$ 58,492	$ 59,980
Interest-earning time deposits	15,744	16,461
Investment securities, held to maturity	210,112	200,448
Loans held for sale	1,038	3,094
Loans (excluding loan level hedges), net	3,005,305	2,828,012
Stock in FHLB	18,073	18,105
Interest receivable	14,239	13,059
Liabilities
Non-interest bearing deposits	642,129	601,805
Interest bearing deposits	2,497,247	2,279,198
Borrowings	550,384	564,157
Subordinated debentures	37,837	37,653
Interest payable	2,031	886
Carrying Amount [Member]
Assets
Cash and due from banks	58,492	76,441
Interest-earning time deposits	15,744	16,461
Investment securities, held to maturity	210,112	200,448
Loans held for sale	1,038	3,094
Loans (excluding loan level hedges), net	2,786,351	2,664,211
Stock in FHLB	18,073	18,105
Interest receivable	14,239	13,059
Liabilities
Non-interest bearing deposits	642,129	601,805
Interest bearing deposits	2,497,247	2,279,198
Borrowings	550,384	564,157
Subordinated debentures	37,837	37,653
Interest payable	2,031	886
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets
Cash and due from banks	58,492	76,441
Liabilities
Non-interest bearing deposits	642,129	601,805
Significant Other Observable Inputs (Level 2) [Member]
Assets
Interest-earning time deposits	15,542	16,632
Investment securities, held to maturity	208,273	201,085
Stock in FHLB	18,073	18,105
Interest receivable	14,239	13,059
Liabilities
Interest bearing deposits	2,377,274	2,156,487
Borrowings	542,311	560,057
Subordinated debentures	35,711	35,994
Interest payable	2,031	886
Significant Unobservable Inputs (Level 3) [Member]
Assets
Loans held for sale	1,038	3,094
Loans (excluding loan level hedges), net	$ 2,681,741	$ 2,589,064

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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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Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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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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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 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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