Condensed Consolidated Balance Sheets - USD ($) $ in Thousands		Jun. 30, 2018	Dec. 31, 2017
CURRENT ASSETS:
Cash and cash equivalents, unrestricted		$ 33,175	$ 18,110
Restricted cash		789	789
Restricted short-term investments		4,570	5,070
Short-term investments		151,571	156,178
Total cash and cash equivalents, restricted cash and short-term investments		190,105	180,147
Student receivables, net of allowance for doubtful accounts of $22,098 and $20,533 as of June 30, 2018 and December 31, 2017, respectively		24,992	18,875
Receivables, other, net		1,948	1,163
Prepaid expenses		10,957	7,722
Inventories		914	1,112
Other current assets		1,607	1,319
Assets of discontinued operations		171	382
Total current assets		230,694	210,720
NON-CURRENT ASSETS:
Property and equipment, net of accumulated depreciation of $196,487 and $213,825 as of June 30, 2018 and December 31, 2017, respectively		30,829	33,230
Goodwill		87,356	87,356
Intangible assets, net of amortization of $1,400 as of both June 30, 2018 and December 31, 2017		7,900	7,900
Student receivables, net of allowance for doubtful accounts of $2,170 and $2,001 as of June 30, 2018 and December 31, 2017, respectively		2,334	2,548
Deferred income tax assets, net		91,443	98,084
Other assets		6,649	5,673
Assets of discontinued operations		1,585	1,585
TOTAL ASSETS	[1]	458,790	447,096
CURRENT LIABILITIES:
Accounts payable		11,297	8,515
Accrued expenses:
Payroll and related benefits		22,895	32,910
Advertising and marketing costs		9,945	9,245
Income taxes		1,762	2,185
Other		33,834	31,233
Deferred revenue		23,050	22,897
Liabilities of discontinued operations		3,125	5,701
Total current liabilities		105,908	112,686
NON-CURRENT LIABILITIES:
Deferred rent obligations		14,827	15,277
Other liabilities		15,138	22,143
Liabilities of discontinued operations			785
Total non-current liabilities		29,965	38,205
STOCKHOLDERS' EQUITY:
Preferred stock, $0.01 par value; 1,000,000 shares authorized; none issued or outstanding
Common stock, $0.01 par value; 300,000,000 shares authorized; 85,115,123 and 84,279,533 shares issued, 69,723,487 and 69,117,803 shares outstanding as of June 30, 2018 and December 31, 2017, respectively		851	843
Additional paid-in capital		624,869	621,008
Accumulated other comprehensive loss		(356)	(164)
Accumulated deficit		(81,874)	(108,127)
Treasury stock, at cost; 15,391,636 and 15,161,730 shares as of June 30, 2018 and December 31, 2017, respectively		(220,573)	(217,355)
Total stockholders' equity		322,917	296,205
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY		$ 458,790	$ 447,096

[1] Total assets do not include intercompany receivable or payable activity between schools and corporate and investments in subsidiaries.