Loans and Allowance for Loan Losses - Schedule of Activity in Loss Share Receivable (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Receivables [Abstract]
Balance, January 1			$ 113,834	$ 177,844
Amortization	(3,321)		(7,229)
Charge-offs, write-downs and other losses) recoveries			(1,048)	(1,209)
External expenses qualifying under loss share agreement			2,841	6,307
Changes due to changes in cash flow projections			(7,875)	2,877
Settlement of disallowed loss claims			(10,268)
Payments received from the FDIC				(33,919)
Ending balance	$ 90,255	$ 151,900	$ 90,255	$ 151,900