License and Collaboration Agreements (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
License, collaboration, and other revenue
License, collaboration and other revenue	$ 7,827	$ 6,506
Affymax Inc [Member] | OMONTYS [Member]
License, collaboration, and other revenue
License, collaboration and other revenue	2,217	451
Hoffmann-La Roche [Member] | PEGASYS and MIRCERA [Member]
License, collaboration, and other revenue
License, collaboration and other revenue	1,380	1,283
Amgen Inc [Member] | Neulasta [Member]
License, collaboration, and other revenue
License, collaboration and other revenue	1,250	1,250
Bayer Healthcare LLC [Member] | BAY41-6551 (Amikacin Inhale) [Member]
License, collaboration, and other revenue
License, collaboration and other revenue	742	750
Baxter Healthcare [Member] | Hemophilia [Member]
License, collaboration, and other revenue
License, collaboration and other revenue	684	368
Other [Member]
License, collaboration, and other revenue
License, collaboration and other revenue	$ 1,554	$ 2,404