Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 17,217	$ 14,136
Short-term investments	56,980	56,976
Accounts and other receivables (net of allowances for doubtful accounts of $26 and $9)	1,348	598
Deferred income taxes	7,784	7,784
Prepaid expenses and other current assets	1,094	690
Total current assets	84,423	80,184
Property and equipment, net	1,364	944
Deferred income tax assets	28,031	29,066
Intangibles and other assets, net	345	381
Total assets	114,163	110,575
Current liabilities:
Accounts payable	1,366	682
Accrued compensation	2,060	4,680
Other current liabilities	2,119	1,653
Deferred revenue	18,020	8,920
Total current liabilities	23,565	15,935
Long-term deferred revenue	10,462	13,441
Other long-term liabilities	476	528
Total liabilities	34,503	29,904
Contingencies (Note 12)
Stockholders' equity:
Common stock and additional paid-in capital - $0.001 par value; 100,000,000 shares authorized; 34,092,042 and 33,619,766 shares issued, respectively; 28,493,004 and 28,637,022 shares outstanding, respectively	202,002	198,057
Accumulated other comprehensive income	114	112
Accumulated deficit	(84,896)	(86,929)
Treasury stock at cost: 5,599,038 and 4,982,744 shares, respectively	(37,560)	(30,569)
Total stockholders' equity	79,660	80,671
Total liabilities and stockholders' equity	$ 114,163	$ 110,575