Variable Interest Entities - Schedule of Payments Made to Entity Related to Guarantee Obligations (Detail) - CUSO RSA [Member] - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2015		Sep. 30, 2014		Sep. 30, 2015		Sep. 30, 2014
Variable Interest Entity [Line Items]
Regular Payments	$ 0	[1]	$ 1,809	[2]	$ 3,840	[3]	$ 4,556	[2]
Discharge Payments	0		0		9,253		0
Net guarantee obligation payments	$ 0		$ 1,809		$ 13,093		$ 4,556

[1] As described above, we deferred payment of $2,574 of Regular Payments, that otherwise would have been due during this period, to January 2016. In addition, the amount of the recoveries of charged-off loans received by the CUSO during this period that are due but have not been paid to us and that we expect to offset against these Regular Payments was $351.

[2] This amount is net of $156 of recoveries from charged-off loans owed to us that we offset against amounts owed by us under the CUSO RSA.

[3] This amount is net of $521 of recoveries from charged-off loans owed to us that we offset against amounts owed by us under the CUSO RSA. In addition, we deferred payment of $3,402 of Regular Payments, that otherwise would have been due during this period, to January 2016. We also expect to utilize the amount of recoveries of charged-off loans received by the CUSO during this period that has not been paid to us, which totaled approximately $468, to offset against amounts that we expect to pay under the CUSO RSA in January 2016.