Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Cash flows from operating activities:
Net loss	$ (75,382)	$ (72,415)
Adjustments to reconcile net loss to net cash used in operating activities:
Non-cash interest expense on liability related to sale of future royalties	7,278
Non-cash royalty revenue related to sale of future royalties	(3,469)
Stock-based compensation	8,035	9,682
Depreciation and amortization	6,952	7,649
Impairment of long-lived assets	1,675
Other non-cash transactions	565	620
Changes in operating assets and liabilities:
Accounts receivable	(6,423)	16,642
Inventory	(2,059)	(2,531)
Other assets	8,176	(2,191)
Accounts payable	80	(3,149)
Accrued compensation	(2,288)	183
Accrued expenses	191	2,371
Accrued clinical trial expenses	654	1,688
Deferred revenue	1,075	(7,549)
Other liabilities	(269)	(658)
Net cash used in operating activities	(55,209)	(49,658)
Cash flows from investing activities:
Purchases of investments	(120,410)	(509,681)
Maturities of investments	179,766	156,962
Sales of investments		180,478
Purchases of property and equipment	(3,172)	(6,845)
Net cash provided by (used in) investing activities	56,184	(179,086)
Cash flows from financing activities:
Payments of loan and capital lease obligations	(1,151)	(934)
Proceeds from sale of future royalties, net of transaction costs	119,589
Issuance of common stock, net of issuance costs	1,337	223,549
Net cash provided by financing activities	119,775	222,615
Effect of exchange rates on cash and cash equivalents	92
Net increase (decrease) in cash and cash equivalents	120,842	(6,129)
Cash and cash equivalents at beginning of period	15,312	17,755
Cash and cash equivalents at end of period	136,154	11,626
Supplemental Cash Flow Information [Abstract]
Cash paid for interest	$ 5,179	$ 5,371