Fair Value of Financial Instruments - Summary of Estimated Fair Values of Financial Instruments (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Assets
Cash and due from banks	$ 63,591	$ 76,441
Investment securities, held to maturity	206,689	200,448
Loans held for sale	1,973	3,094
Loans (excluding loan level hedges), net	2,848,795	2,824,827
Stock in FHLB	18,105	18,105
Interest receivable	12,044	16,244
Liabilities
Non-interest bearing deposits	602,175	601,805
Interest bearing deposits	2,331,501	2,279,198
Borrowings	520,300	564,157
Subordinated debentures	37,699	37,653
Interest payable	1,216	886
Carrying Amount [Member]
Assets
Cash and due from banks	63,591	76,441
Investment securities, held to maturity	206,689	200,448
Loans held for sale	1,973	3,094
Loans (excluding loan level hedges), net	2,685,306	2,661,026
Stock in FHLB	18,105	18,105
Interest receivable	12,044	16,244
Liabilities
Non-interest bearing deposits	602,175	601,805
Interest bearing deposits	2,331,501	2,279,198
Borrowings	520,300	564,157
Subordinated debentures	37,699	37,653
Interest payable	1,216	886
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets
Cash and due from banks	63,591	76,441
Liabilities
Non-interest bearing deposits	602,175	601,805
Significant Other Observable Inputs (Level 2) [Member]
Assets
Investment securities, held to maturity	203,896	201,085
Stock in FHLB	18,105	18,105
Interest receivable	12,044	16,244
Liabilities
Interest bearing deposits	2,195,544	2,156,487
Borrowings	514,777	560,057
Subordinated debentures	35,546	35,994
Interest payable	1,216	886
Significant Unobservable Inputs (Level 3) [Member]
Assets
Loans held for sale	1,973	3,094
Loans (excluding loan level hedges), net	$ 2,529,000	$ 2,585,879

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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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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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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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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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The aggregate of all domestic and foreign interest-bearing deposit liabilities.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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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 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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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. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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