Loans and Allowance for Loan Losses - Schedule of Activity in Loss Share Receivable (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Receivables [Abstract]
Balance, January 1	$ 177,844	$ 231,085
Accretion (amortization)	(590)	5,000
Charge-offs, write-downs and other losses	(190)	36,685
External expenses qualifying under loss share agreement	7,918	7,422
Payments received from the FDIC	(60,886)	(84,130)
Ending balance	$ 124,096	$ 196,062