Quantitative information about assets and liabilities measured at fair value on a recurring basis using level 3 inputs (Details)	9 Months Ended
	Sep. 30, 2012
Fair Value Inputs Assets Quantitative Information [Line Items]
Contingent Consideration Receivable Fair Value Valuation Technique	Income approach (probability weighted discounted cash flow)
Contingent Consideration Receivable Fair Value Significant Unobservable Input 1	Probability weightings applied to different sales scenarios
Contingent Consideration Receivable Fair Value Significant Unobservable Input 2	Future forecast royalties receivable at relevant contractual royalty rates
Contingent Consideration Receivable Fair Value Significant Unobservable Input 3	Assumed market participant discount rate
Fair Value Inputs Liabilities Quantitative Information [Line Items]
Contingent Consideration Payable Fair Value Valuation Technique	Income approach (probability weighted discounted cash flow)
Contingent Consideration Payable Fair Value Significant Unobservable Input 1	Cumulative probability of milestones being achieved
Contingent Consideration Payable Fair Value Significant Unobservable Input 2	Assumed market participant discount rate
Contingent Consideration Payable Fair Value Significant Unobservable Input 3	Periods in which milestones are expected to be achieved
Contingent Consideration Payable Fair Value Significant Unobservable Input 4	Forecast quarterly royalties payable on net sales of relevant products
Probability Weightings Applied To Different Sales Scenarios [Member]
Fair Value Inputs Assets Quantitative Information [Line Items]
Contingent Consideration Receivables Fair Value Range	5 to 45 percent
Future forecast royalties receivable at relevant contractual royalty rates
Fair Value Inputs Assets Quantitative Information [Line Items]
Contingent Consideration Receivables Fair Value Range	$5 million to $183 million
Assumed Market Participant Discount Rate [Member]
Fair Value Inputs Assets Quantitative Information [Line Items]
Contingent Consideration Receivables Fair Value Range	5.6 percent
Fair Value Inputs Liabilities Quantitative Information [Line Items]
Contingent Consideration Payable Fair Value Range	7.4 to 9.1 percent (Weighted average)
Cumulative Probability Of Milestones Being Achieved [Member]
Fair Value Inputs Liabilities Quantitative Information [Line Items]
Contingent Consideration Payable Fair Value Range	19 to 45 percent (Weighted average)
Periods In Which Milestones Are Expected To Be Achieved [Member]
Fair Value Inputs Liabilities Quantitative Information [Line Items]
Contingent Consideration Payable Fair Value Range	2013 to 2028
Forecast quarterly royalties payable on net sales of relevant products
Fair Value Inputs Liabilities Quantitative Information [Line Items]
Contingent Consideration Payable Fair Value Range	$2.9 million to $4.4 million