Fair Value of Financial Instruments - Summary of Estimated Fair Values of Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Assets
Cash and due from banks	$ 48,650	$ 43,476
Investment securities, held to maturity	187,629	165,767
Loans held for sale	7,917	6,143
Loans excluding loan level hedges, net	1,739,713	1,365,885
Stock in FHLB and FRB	13,823	11,348
Interest receivable	10,535	8,246
Liabilities
Non-interest bearing deposits	335,955	267,667
Subordinated debentures	32,797	32,642
Interest payable	507	497
Carrying Amount [Member]
Assets
Cash and due from banks	48,650	43,476
Investment securities, held to maturity	187,629	165,767
Loans held for sale	7,917	6,143
Loans excluding loan level hedges, net	1,619,125	1,260,608
Stock in FHLB and FRB	13,823	11,348
Interest receivable	10,535	8,246
Liabilities
Non-interest bearing deposits	335,955	267,667
Interest-bearing deposits	1,544,198	1,214,652
Borrowings	449,347	351,198
Subordinated debentures	32,797	32,642
Interest payable	507	497
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets
Cash and due from banks	48,650	43,476
Liabilities
Non-interest bearing deposits	335,955	267,667
Significant Other Observable Inputs (Level 2) [Member]
Assets
Investment securities, held to maturity	193,703
Stock in FHLB and FRB	13,823	11,348
Interest receivable	10,535	8,246
Liabilities
Interest-bearing deposits	1,461,314	1,158,912
Borrowings	441,547	348,597
Subordinated debentures	32,996	32,669
Interest payable	507	497
Significant Unobservable Inputs (Level 3) [Member]
Assets
Investment securities, held to maturity		169,904
Loans held for sale	7,917	6,143
Loans excluding loan level hedges, net	$ 1,703,506	$ 1,295,133

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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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Amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

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Total amount of interest-bearing domestic deposit liabilities, which may include brokered, retail, demand, checking, notice of withdrawal, money market and other interest-bearing deposits.

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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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