Commitments and Contingencies - Estimated Amounts of Regular, Discharge Payments Expect to Pay and Estimated Recoveries from Charged-off Loans (Parenthetical) (Detail) (CUSO RSA [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended		0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Mar. 19, 2015
Summary Of Projections Of Estimated Payments And Recoveries [Line Items]
Discharge Payments	$ 2,577	$ 912
Subsequent Event [Member] | Fifth Amendment [Member]
Summary Of Projections Of Estimated Payments And Recoveries [Line Items]
Discharge Payments			$ 2,709