Debt - Total Amount of Interest Expense and Discount Accretion on PEAKS Senior Debt (Detail) - PEAKS Senior Debt [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Debt Instrument [Line Items]
Contractual interest expense	$ 1,038	$ 1,604
Discount accretion	720	1,655
Total interest expense	$ 1,758	$ 3,259