CONDENSED CONSOLIDATED STATEMENTS OF INCOME (unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2012
Income Statement [Abstract]
Revenue	$ 260,459	$ 328,061	$ 545,521		$ 667,270
Costs and expenses:
Cost of educational services	123,541	140,067	247,717		275,008
Student services and administrative expenses	98,335	105,895	200,056		207,214
Legal and other investigation costs	213	873	1,713		873
Loss related to loan program guarantees	0	3,906	3,803		6,960
Provision for PEAKS Trust student loan losses	4,319	0	4,319		0
Total costs and expenses	226,408	250,741	457,608		490,055
Operating income	34,051	77,320	87,913		177,215
(Loss) on consolidation of PEAKS Trust	0	0	(73,248)		0
Interest income	25	502	59		1,183
Interest (expense)	(7,369)	(1,254)	(10,943)		(1,801)
Income before provision for income taxes	26,707	76,568	3,781		176,597
Provision for income taxes	6,503	30,627	849		70,011
Net income	$ 20,204	$ 45,941	$ 2,932	$ 32,384	$ 106,586
Earnings per share:
Basic	$ 0.86	$ 1.96	$ 0.13		$ 4.37
Diluted	$ 0.86	$ 1.95	$ 0.12		$ 4.34
Weighted average shares outstanding:
Basic	23,414	23,390	23,406		24,405
Diluted	23,550	23,529	23,516		24,583