Revenue from collaboration Agreement (Details Textuals) (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 (Textuals) [Abstract]
Revenue From Collaboration Agreement	$ 67,956	$ 68,773	$ 135,101	$ 131,676
Notice period to terminate the agreement with Bayer			30 days
Maximum period for notice to terminate the agreement with Bayer			60 days