Revenue (Summary of Revenue Recognized) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Disaggregation of Revenue [Line Items]
Revenue	$ 6,740.1	$ 5,499.4	$ 13,545.7	$ 11,359.2
Net product revenue
Disaggregation of Revenue [Line Items]
Revenue	6,070.5	5,077.7	12,390.5	10,481.2
Collaboration and other revenue
Disaggregation of Revenue [Line Items]
Revenue	669.6	421.7	1,155.2	878.0
Collaboration and other revenue associated with prior period transfers of intellectual property
Disaggregation of Revenue [Line Items]
Revenue	$ 31.0	$ 34.7	$ 73.9	$ 70.0