Debt - Total Amount of Interest Expense and Discount Accretion on PEAKS Senior Debt (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Debt Instrument [Line Items]
Interest expense	$ 7,211	$ 7,369	$ 19,023	$ 10,943
PEAKS Senior Debt [Member]
Debt Instrument [Line Items]
Interest expense	6,456	6,256	17,473	8,678
Discount accretion	$ 2,389	$ 1,381	$ 8,841	$ 2,033