Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Current assets
Cash and cash equivalents	$ 65,238	$ 55,824
Restricted cash, cash equivalents and investments	67,840	64,368
Investments	100,784	108,420
Accounts receivable, net	7,605	7,217
Income taxes receivable	1	3,599
Deferred income taxes	6,149	5,159
Other current assets	19,428	19,116
Total current assets	267,045	263,703
Property and equipment, net	478,170	339,596
Prepaid royalties	3,650	4,641
Goodwill	2,941	2,941
Other assets	3,907	5,219
Total assets	755,713	616,100
Current liabilities
Accounts payable	22,715	24,231
Accrued compensation and benefits	23,995	20,093
Accrued liabilities	13,533	14,554
Income taxes payable	4,906	7
Student deposits	69,584	66,772
Deferred revenue	36,868	32,816
Due to related parties	403	454
Current portion of capital lease obligations	91	89
Current portion of notes payable	6,616	6,607
Total current liabilities	178,711	165,623
Capital lease obligations, less current portion	406	497
Other noncurrent liabilities	4,513	6,811
Deferred income taxes, non-current	15,974	11,832
Notes payable, less current portion	79,877	86,493
Total liabilities	279,481	271,256
Commitments and contingencies
Stockholders' equity
Preferred stock, $0.01 par value, 10,000 shares authorized; 0 shares issued and outstanding at December 31, 2014 and 2013
Common stock, $0.01 par value, 100,000 shares authorized; 49,746 and 48,890 shares issued and 46,744 and 46,045 shares outstanding at December 31, 2014 and 2013, respectively	497	489
Treasury stock, at cost, 3,002 and 2,845 shares of common stock at December 31, 2014 and 2013, respectively	(53,770)	(48,432)
Additional paid-in capital	158,549	132,904
Accumulated other comprehensive (loss) income	(35)	358
Retained earnings	370,991	259,525
Total stockholders' equity	476,232	344,844
Total liabilities and stockholders' equity	$ 755,713	$ 616,100