Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statements of Income [Abstract]
Revenues	$ 112,720	$ 108,487	$ 227,632	$ 219,653
Costs and expenses:
Instruction and educational support	61,656	61,782	123,072	119,880
Marketing	19,226	17,748	37,944	36,046
Admissions advisory	4,779	4,131	9,495	8,480
General and administration	13,205	11,930	24,824	22,259
Total costs and expenses	98,866	95,591	195,335	186,665
Income from operations	13,854	12,896	32,297	32,988
Investment income	253	112	434	212
Interest expense	160	160	319	320
Income before income taxes	13,947	12,848	32,412	32,880
Provision for income taxes	3,645	5,062	11,532	12,674
Net income	$ 10,302	$ 7,786	$ 20,880	$ 20,206
Earnings per share:
Basic	$ 0.96	$ 0.73	$ 1.96	$ 1.91
Diluted	$ 0.92	$ 0.72	$ 1.87	$ 1.87
Weighted average shares outstanding:
Basic	10,680	10,610	10,655	10,603
Diluted	11,190	10,799	11,155	10,790