Fair Value - Assets and Liabilities Measured at Fair Value (Parenthetical) (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in impaired loans subject to fair value	$ 41,052	$ 54,748
Specific allowance within the allowance for loan losses	0	0
Charge-offs related to impaired loans	31	7,344
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in impaired loans subject to fair value	$ 1,275	$ 20,305