Activity in Allowance for Losses on Covered Loans (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Valuation Allowance [Line Items]
Balance, beginning of period	$ 51,311	$ 33,323
Provision for losses on covered loans	30,758	62,988	100,420
Balance, end of period	64,069	51,311	33,323
Covered Loans
Valuation Allowance [Line Items]
Provision for losses on covered loans	$ 12,758	$ 17,988	$ 21,420