Borrowings - Borrowings (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Debt Disclosure [Abstract]
Federal Home Loan Bank advances, variable and fixed rates ranging from 0.45% to 7.53%, due at various dates through November 15, 2024	$ 158,948	$ 116,473
Securities sold under agreements to repurchase	154,399	139,725
Federal funds purchased	136,000	95,000
Total borrowings	$ 449,347	$ 351,198

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
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Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

+ References

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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

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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.

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