Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 40,302	$ 48,544
Marketable securities	48,206
Marketable securities - restricted	279	245
Accounts receivable	11
Interest receivable	664
Inventory	1,152
Prepaid expenses and other	983	466
Deferred financing costs, current	144	144
Total current assets	91,741	49,399
Property and equipment, net	1,421	1,310
Purchased patents, net	683	912
Other assets	55	55
Deferred financing costs, long-term	89	2,054
Total assets	93,989	53,730
Current liabilities:
Accounts payable and accrued expenses	10,666	11,763
Deferred revenue	508	232
Secured notes payable, net of discount	11,809	6,775
Total current liabilities	22,983	18,770
Deferred revenue, net of current portion	309	465
Secured notes payable, net of current portion and discount	11,088	22,711
Other non-current liabilities	1,509	1,399
Supplemental executive retirement plan	279	245
Warrant liability	251	697
Total liabilities	36,419	44,287
Stockholders' equity:
Series A convertible preferred stock, $0.001 par value -49,625,000 and 65,000,000 shares authorized at December 31, 2011 and 2012, respectively; 49,000,000 and zero shares issued and outstanding at December 31, 2011 and 2012 and respectively; aggregate liquidation preference of $69,520 and zero at December 31, 2011 and 2012, respectively		49
Common stock, $0.001 par value -62,625,000 and 130,000,000 shares authorized at December 31, 2011 and 2012, respectively; 1,662,321 and 30,621,869 shares issued and outstanding at December 31, 2011 and 2012, respectively	31	2
Additional paid-in capital	143,851	49,362
Accumulated other comprehensive income (loss)	(57)	1
Accumulated deficit	(86,255)	(39,971)
Total stockholders' equity	57,570	9,443
Total liabilities and stockholders' equity	$ 93,989	$ 53,730