Fair Value of Financial Instruments - Summary of Estimated Fair Values of the Financial Instruments (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Assets
Cash and due from banks	$ 40,500	$ 30,735
Investment securities, held to maturity	9,910
Loans held for sale	4,594	13,744
Interest receivable	7,506	7,716
Liabilities
Non-interest bearing deposits	223,354	209,200
Interest payable	488	560
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets
Cash and due from banks	40,500	30,735
Investment securities, held to maturity
Loans held for sale
Loans excluding loan level hedges, net
Stock in FHLB and FRB
Interest receivable
Liabilities
Non-interest bearing deposits	223,354	209,200
Interest-bearing deposits
Borrowings
Subordinated debentures
Interest payable
Significant Other Observable Inputs (Level 2) [Member]
Assets
Cash and due from banks
Investment securities, held to maturity
Loans held for sale
Loans excluding loan level hedges, net
Stock in FHLB and FRB	14,184	13,333
Interest receivable	7,506	7,716
Liabilities
Non-interest bearing deposits
Interest-bearing deposits	1,060,853	1,092,184
Borrowings	245,043	352,891
Subordinated debentures	32,483	32,268
Interest payable	488	560
Significant Unobservable Inputs (Level 3) [Member]
Assets
Cash and due from banks
Investment securities, held to maturity	9,910
Loans held for sale	4,594	13,744
Loans excluding loan level hedges, net	996,408	1,118,255
Stock in FHLB and FRB
Interest receivable
Liabilities
Non-interest bearing deposits
Interest-bearing deposits
Borrowings
Subordinated debentures
Interest payable
Carrying Amount [Member]
Assets
Cash and due from banks	40,500	30,735
Investment securities, held to maturity	9,910
Loans held for sale	4,594	13,744
Loans excluding loan level hedges, net	973,300	1,089,215
Stock in FHLB and FRB	14,184	13,333
Interest receivable	7,506	7,716
Liabilities
Non-interest bearing deposits	223,354	209,200
Interest-bearing deposits	1,104,966	1,084,953
Borrowings	242,505	345,764
Subordinated debentures	32,448	32,331
Interest payable	$ 488	$ 560

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

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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 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 of loans held for sale, including but not limited to, commercial and consumer loans. 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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The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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