Consolidated Income Statements (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Income Statement [Abstract]
Net revenue	$ 152,399	$ 133,568	$ 435,892	$ 369,959
Costs and expenses:
Instructional costs and services	64,704	57,354	186,448	161,584
Admissions advisory and related, including $953 and $645 for the three months ended September 30, 2013 and 2012, respectively, and $2,574 and $1,666 for the nine months ended September 30, 2013 and 2012, respectively, to related parties	24,578	22,342	70,917	62,702
Advertising	15,498	12,909	45,947	38,015
Marketing and promotional	1,299	1,199	4,117	3,047
General and administrative	9,035	8,561	26,064	23,806
Total costs and expenses	115,114	102,365	333,493	289,154
Operating income	37,285	31,203	102,399	80,805
Interest expense	(528)	(154)	(1,635)	(439)
Interest and other income	1,502	16	3,759	52
Income before income taxes	38,259	31,065	104,523	80,418
Income tax expense	15,714	12,594	41,969	31,880
Net income	$ 22,545	$ 18,471	$ 62,554	$ 48,538
Earnings per share:
Basic income per share	$ 0.50	$ 0.42	$ 1.40	$ 1.09
Diluted income per share	$ 0.49	$ 0.41	$ 1.36	$ 1.07
Basic weighted average shares outstanding	44,963	44,365	44,631	44,395
Diluted weighted average shares outstanding	46,424	45,339	45,936	45,220