Fair Value of Financial Instruments - Carrying Value and Fair Value Measurements of Financial Instruments (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	$ 3,502	$ 9,541
Investment in short-term receivables	246,817	81,044
Investment securities available for sale	277,719	405,355
Investment securities held to maturity	94,904
Loans and loans held for sale	6,577	25,860
Cash surrender value of bank-owned life insurance	26,187	25,506
Derivative instruments	1,200
Deposits, noninterest-bearing	291,080	239,538
Deposits, interest-bearing	2,439,727	2,028,990
Short-term borrowings and repurchase agreements	75,957	36,287
Derivative instruments		6,900
Total Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	28,140	26,471
Short-term investments	3,502	9,541
Investment in short-term receivables	246,817	81,044
Investment securities available for sale	277,719	405,355
Investment securities held to maturity	90,966
Loans and loans held for sale	2,344,475	1,939,622
Cash surrender value of bank-owned life insurance	26,187	25,506
Deposits, noninterest-bearing	291,080	239,538
Deposits, interest-bearing	2,380,985	2,035,696
Short-term borrowings and repurchase agreements	84,382	58,087
Long-term borrowings	55,616	77,870
Derivative instruments	4,317	6,854
Carrying Amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	28,140	26,471
Short-term investments	3,502	9,541
Investment in short-term receivables	246,817	81,044
Investment securities available for sale	277,719	405,355
Investment securities held to maturity	94,904
Loans and loans held for sale	2,364,354	1,948,077
Cash surrender value of bank-owned life insurance	26,187	25,506
Derivative instruments	1,157
Deposits, noninterest-bearing	291,080	239,538
Deposits, interest-bearing	2,439,727	2,028,990
Short-term borrowings and repurchase agreements	84,382	58,087
Long-term borrowings	55,110	75,220
Derivative instruments	4,317	6,854
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	28,140	26,471
Short-term investments	3,502	9,541
Investment in short-term receivables	246,817	81,044
Investment securities available for sale	0
Investment securities held to maturity	0
Loans and loans held for sale	0
Cash surrender value of bank-owned life insurance	0
Deposits, noninterest-bearing	0
Deposits, interest-bearing	0
Short-term borrowings and repurchase agreements	0
Long-term borrowings	0
Derivative instruments	0
Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	0
Short-term investments	0
Investment securities available for sale	277,719	405,355
Investment securities held to maturity	90,966
Loans and loans held for sale	0
Cash surrender value of bank-owned life insurance	26,187	25,506
Deposits, noninterest-bearing	291,080	239,538
Deposits, interest-bearing	0
Short-term borrowings and repurchase agreements	84,382	58,087
Long-term borrowings	0
Derivative instruments	4,317	6,854
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	0
Short-term investments	0
Investment securities available for sale	0
Loans and loans held for sale	2,344,475	1,939,622
Cash surrender value of bank-owned life insurance	0
Deposits, noninterest-bearing	0
Deposits, interest-bearing	2,380,985	2,035,696
Short-term borrowings and repurchase agreements	0
Long-term borrowings	55,616	77,870
Derivative instruments	$ 0

Cash And Due From Banks Including Receivables From Sale Of Investments

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value 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 mortgage loans held for sale. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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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 total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement.

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Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy.

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