Financial Instruments and Fair Value Measurement (Details) (USD $)	Mar. 07, 2012 Avila Therapeutics, Inc.	Jun. 30, 2012 Avila Therapeutics, Inc. Maximum	Mar. 07, 2012 Avila Therapeutics, Inc. Maximum	Jun. 30, 2012 Gloucester Pharmaceuticals, Inc. Maximum	Jun. 30, 2012 Recurring basis Fair Value	Dec. 31, 2011 Recurring basis Fair Value	Jun. 30, 2012 Recurring basis Quoted Price in Active Markets for Identical Assets (Level 1)	Dec. 31, 2011 Recurring basis Quoted Price in Active Markets for Identical Assets (Level 1)	Jun. 30, 2012 Recurring basis Significant Other Observable Inputs (Level 2)	Dec. 31, 2011 Recurring basis Significant Other Observable Inputs (Level 2)	Jun. 30, 2012 Recurring basis Significant Unobservable Inputs (Level 3)	Dec. 31, 2011 Recurring basis Significant Unobservable Inputs (Level 3)
Fair Value of assets and liabilities
Estimated maximum potential payments related to contingent consideration		$ 595,000,000	$ 595,000,000	$ 120,000,000
Assets:
Available-for-sale securities					699,065,000	788,690,000	432,000	560,000	698,633,000	788,130,000
Forward currency contracts					81,765,000	48,561,000			81,765,000	48,561,000
Treasury rate lock agreements					1,816,000				1,816,000
Total assets					782,646,000	837,251,000	432,000	560,000	782,214,000	836,691,000
Liabilities:
Contingent value rights					(77,893,000)	(60,583,000)	(77,893,000)	(60,583,000)
Other acquisition related contingent consideration	169,337,000				(254,555,000)	(76,890,000)					(254,555,000)	(76,890,000)
Total liabilities					$ (332,448,000)	$ (137,473,000)	$ (77,893,000)	$ (60,583,000)			$ (254,555,000)	$ (76,890,000)