CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Net revenue
Licensing and other	$ 248	$ 756	$ 1,113	$ 3,319
Royalty	1,079	1,351	3,374	5,619
Total net revenue	1,327	2,107	4,487	8,938
Cost of net revenue
Licensing and other	53	356	289	1,515
Total cost of net revenue	53	356	289	1,515
Gross profit	1,274	1,751	4,198	7,423
Operating expenses
Research and development	7,026	6,648	21,220	19,369
Selling, general and administrative	1,738	1,952	6,092	6,583
Gain on sale of assets	(1,435)		(3,291)
Total operating expenses	7,329	8,600	24,021	25,952
Loss from operations	(6,055)	(6,849)	(19,823)	(18,529)
Other income and expense, net	61	10	121	44
Loss before income taxes	(5,994)	(6,839)	(19,702)	(18,485)
Income tax provision	79	24	139	59
Net loss	(6,073)	(6,863)	(19,841)	(18,544)
Other comprehensive loss, net of tax:
Net unrealized gains (losses) on available-for-sale securities	27	(23)	25	(15)
Comprehensive loss	$ (6,046)	$ (6,886)	$ (19,816)	$ (18,559)
Net loss per share
Basic and diluted (in dollars per share)	$ (0.15)	$ (0.18)	$ (0.51)	$ (0.49)
Shares used in computing net loss per share
Basic and diluted (in shares)	39,299	38,090	38,919	37,700