Revenue (Summary of Revenue Recognized) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Revenue	$ 6,772.8	$ 5,740.6	$ 20,318.5	$ 17,099.8
Net product revenue
Disaggregation of Revenue [Line Items]
Revenue	6,189.0	5,281.1	18,579.5	15,762.3
Collaboration and other revenue
Disaggregation of Revenue [Line Items]
Revenue	583.8	459.5	1,739.0	1,337.5
Collaboration and other revenue associated with prior period transfers of intellectual property
Disaggregation of Revenue [Line Items]
Revenue	$ 62.1	$ 31.5	$ 136.1	$ 101.5