Revenue from Collaboration Agreement (Details) (USD $) In Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Revenue from Collaboration Agreement [Abstract]
Onyx's share of collaboration commercial profit	$ 58,535	$ 59,978	$ 118,115	$ 115,063
Reimbursement of Onyx's shared marketing expenses	6,687	6,475	11,291	12,299
Royalty revenue	2,734	2,320	5,695	4,314
Revenue from collaboration agreement	$ 67,956	$ 68,773	$ 135,101	$ 131,676