CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Current assets:
Cash and cash equivalents	$ 39,554	$ 37,216
Available-for-sale securities	107,282	101,970
Inventories	3,107	3,225
Prepaid expenses and other assets	1,793	1,648
Current assets of discontinued operations		6
Total current assets	151,736	144,065
Property and equipment, net	320	221
Total assets	152,056	144,286
Current liabilities:
Accounts payable	2,940	2,395
Accrued research and clinical expenses	1,425	2,625
Accrued employee compensation and benefits	3,693	2,820
Accrued and other liabilities	1,274	932
Current liabilities of discontinued operations	1,640	3,512
Total current liabilities	10,972	12,284
Commitments and contingencies
Stockholders' equity:
Preferred stock; $1.00 par value; 5,000 shares authorized; no shares issued and outstanding at December 31, 2011 and 2010
Common stock; $.001 par value; 200,000 shares authorized at December 31, 2011 and 2010; 88,975 and 81,568 shares issued and outstanding at December 31, 2011 and 2010, respectively	89	82
Additional paid-in capital	487,235	432,041
Accumulated other comprehensive income (loss)	25	4
Accumulated deficit	(346,265)	(300,125)
Total stockholders' equity	141,084	132,002
Total liabilities and stockholders' equity	$ 152,056	$ 144,286