Variable Interest Entities - Schedule of Revenue and Expenses of PEAKS Trust (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Variable Interest Entity [Line Items]
Revenue	$ 267,173	$ 259,617	$ 260,459	$ 285,062	$ 305,572	$ 313,791	$ 328,061	$ 339,209	$ 1,072,311	$ 1,286,633	$ 1,499,977
Student services and administrative expenses	101,303	96,182	98,335	101,721	88,995	104,647	105,895	101,319	397,541	400,856	414,156
Provision for PEAKS Trust student loan losses	8,648	16,382	4,319	0					29,349	0	0
Interest expense	7,144	7,190	7,369	3,574	901	1,021	1,254	547	25,277	3,723	1,825
Income (loss) before provision for income taxes	(53,777)	12,760	26,707	(22,926)	(17,814)	69,205	76,568	100,029	(37,236)	227,988	510,333
PEAKS Trust [Member]
Variable Interest Entity [Line Items]
Revenue									12,996
Student services and administrative expenses									5,288
Provision for PEAKS Trust student loan losses									29,349
Interest expense									21,288
Income (loss) before provision for income taxes									$ (42,929)