Other Real Estate Owned - Summary of OREO Valuation Allowance Activity (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Other Real Estate, Valuation Allowance [Roll Forward]
Balance at beginning of period	$ 15,780	$ 24,515	$ 20,583	$ 30,842
Valuation adjustments	746	2,348	1,192	4,627
Sales	(1,717)	(4,472)	(6,966)	(13,078)
Balance at end of period	$ 14,809	$ 22,391	$ 14,809	$ 22,391

The aggregate selling price reductions recognized during an accounting period due to the rendering of deficient or nonconforming services. Allowances are a deduction from gross revenue in arriving at net revenue.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1(d))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration