Borrowings - Summary of Long-Term Borrowings (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Debt Disclosure [Abstract]
Federal Home Loan Bank advances	$ 400,017	$ 400,042
Subordinated notes	84,289	83,155
Junior subordinated debt	58,272	58,246
Long-term debt	$ 542,578	$ 541,443

No definition available.

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- Definition

Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 470

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- Definition

Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

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-Publisher SEC

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-Number 210

-Section 02

-Paragraph 20, 22

-Article 5

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Carrying value as of the balance sheet date of collateralized/uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Subordinated debt places a lender in a lien position behind the primary lender of the company.

+ References

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