CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 20,334	$ 25,013
Short-term investments	35,932	39,918
Accounts and other receivables (net of allowances for doubtful accounts of $15)	1,671	1,213
Prepaid expenses and other current assets	2,940	2,790
Total current assets	60,877	68,934
Property and equipment, net	4,241	4,589
Deferred income tax assets	30,754	24,633
Prepaid income taxes	4,997	6,995
Intangibles and other assets, net	289	264
Total assets	101,158	105,415
Current liabilities:
Accounts payable	2,590	650
Accrued compensation	3,265	4,840
Other current liabilities	3,503	2,999
Deferred revenue	5,689	6,696
Total current liabilities	15,047	15,185
Long-term deferred revenue	1,416	2,516
Other long-term liabilities	882	1,099
Total liabilities	17,345	18,800
Contingencies (Note 12)
Stockholders’ equity:
Common stock and additional paid-in capital — $0.001 par value; 100,000,000 shares authorized; 35,379,275 and 34,845,310 shares issued, respectively; 28,863,381 and 28,329,416 shares outstanding, respectively	217,509	212,115
Accumulated other comprehensive income	141	86
Accumulated deficit	(88,199)	(79,948)
Treasury stock at cost: 6,515,894 shares	(45,638)	(45,638)
Total stockholders’ equity	83,813	86,615
Total liabilities and stockholders’ equity	$ 101,158	$ 105,415