CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 61,974	$ 25,013
Short-term investments	32,931	39,918
Accounts and other receivables (net of allowances for doubtful accounts of $0 and $15)	3,248	1,213
Prepaid expenses and other current assets	2,995	2,790
Total current assets	101,148	68,934
Property and equipment, net	4,068	4,589
Deferred income tax assets	25,510	24,633
Prepaid income taxes	6,502	6,995
Intangibles and other assets, net	395	264
Total assets	137,623	105,415
Current liabilities:
Accounts payable	2,418	650
Accrued compensation	3,242	4,840
Other current liabilities	4,242	2,999
Deferred revenue	7,622	6,696
Total current liabilities	17,524	15,185
Long-term deferred revenue	27,489	2,516
Other long-term liabilities	926	1,099
Total liabilities	45,939	18,800
Contingencies (Note 13)
Stockholders’ equity:
Common stock and additional paid-in capital — $0.001 par value; 100,000,000 shares authorized; 35,439,389 and 34,845,310 shares issued, respectively; 28,817,745 and 28,329,416 shares outstanding, respectively	219,114	212,115
Accumulated other comprehensive income	118	86
Accumulated deficit	(81,181)	(79,948)
Treasury stock at cost: 6,621,644 and 6,515,894 shares, respectively	(46,367)	(45,638)
Total stockholders’ equity	91,684	86,615
Total liabilities and stockholders’ equity	$ 137,623	$ 105,415