Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 272,122	$ 224,057
Marketable securities-available-for-sale	19,052	4,361
Accounts receivable, net	33,197	70,951
Inventory	359	278
Prepaid expenses and other current assets	9,013	9,867
Total current assets	333,743	309,514
Inventory	14,948	8,475
Property and equipment, net	6,201	6,348
Intangible and other assets, net	2,508	6,082
Total assets	357,400	330,419
Current liabilities:
Accounts payable	18,212	13,961
Accrued compensation	17,957	22,899
Interest payable	6,087	4,750
Accrued and other current liabilities	41,739	28,385
Deferred revenue-Collaborative agreements	25,503	66,079
Total current liabilities	109,498	136,074
Convertible senior notes	187,136	322,043
Convertible subordinated note		9,033
Other liabilities	3,392
Deferred revenue-Collaborative agreements	28,583	38,226
Total liabilities	328,609	505,376
Stockholders' equity (deficit):
Preferred stock, $0.001 par value; 5,000,000 shares authorized; none issued or outstanding as of September 30, 2013 and December 31, 2012
Common stock, $0.001 par value; 400,000,000 shares authorized; 160,881,043 and 133,462,185 shares issued and outstanding as of September 30, 2013 and December 31, 2012, respectively	161	133
Additional paid-in capital	1,720,788	1,476,922
Accumulated other comprehensive gain	2,008	1,878
Accumulated deficit	(1,694,166)	(1,653,890)
Total stockholders' equity (deficit)	28,791	(174,957)
Total liabilities and stockholders'equity (deficit)	$ 357,400	$ 330,419