Condensed Balance Sheets (Unaudited) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Current assets
Cash and cash equivalents	$ 28,395	$ 21,008
Short-term investments	2,458	33,809
Accounts receivable, net	1,953	5,584
Inventory	980	991
Other current assets	3,167	1,882
Total current assets	36,953	63,274
Property and equipment, net	956	755
Intangibles, net	1,190	1,102
Total assets	39,099	65,131
Current liabilities
Accounts payable	1,674	1,709
Accrued liabilities	7,094	5,699
Deferred revenue, current portion	0	3,459
Total current liabilities	8,768	10,867
Deferred revenue, non-current portion	464	0
Commitments and contingencies (see Note 6)
Stockholders' equity
Preferred stock, $0.0001 par value; 10,000 shares authorized, none issued and outstanding	0	0
Common stock, $0.0001 par value; 100,000 shares authorized; 47,198 and 45,004 shares outstanding at June 30, 2011 and December 31, 2010, respectively	5	5
Additional paid-in capital	278,701	271,112
Accumulated deficit	(248,839)	(216,852)
Accumulated other comprehensive income (loss)	0	(1)
Total stockholders' equity	29,867	54,264
Total liabilities and stockholders' equity	$ 39,099	$ 65,131