Variable Interest Entities - Schedule of Revenue and Expenses of PEAKS Trust (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Variable Interest Entity [Line Items]
Student services and administrative expenses	$ 98,335	$ 105,895	$ 200,056	$ 207,214
Provision for PEAKS Trust student loan losses	4,319	0	4,319	0
Interest expense	7,369	1,254	10,943	1,801
Income (loss) before provision for income taxes	26,707	76,568	3,781	176,597
PEAKS Trust [Member]
Variable Interest Entity [Line Items]
Revenue	4,104		5,464
Student services and administrative expenses	1,559		2,078
Provision for PEAKS Trust student loan losses	4,319		4,319
Interest expense	6,256		8,678
Income (loss) before provision for income taxes	$ (8,030)		$ (9,611)