Composition of Borrowings (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Federal funds purchased	$ 0us-gaap_FederalFundsPurchased	$ 16,000us-gaap_FederalFundsPurchased
Securities sold under agreements to repurchase:
Securities sold under agreements to repurchase	121,742	118,308
FHLB advances	90,000	150,000
Subordinated debt	15,464us-gaap_SubordinatedDebt	15,464us-gaap_SubordinatedDebt
Other debt	2,535	624
Total borrowings	229,741	300,396
Retail
Securities sold under agreements to repurchase:
Securities sold under agreements to repurchase	71,742	68,308
Wholesale
Securities sold under agreements to repurchase:
Securities sold under agreements to repurchase	$ 50,000	$ 50,000

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- Definition

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-SubTopic 470

-Section 45

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- Definition

Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

+ References

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- Definition

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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13(1))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 20

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-Paragraph 3

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-SubTopic 20

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Subparagraph 1

-Article 9

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-Publisher FASB

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-Subparagraph (SX 210.4-08.(m)(1)(a)(i))

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- Definition

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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