Fair Value Measurements (Details 1) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Notes payable, carrying value	$ 6,496.5	$ 6,499.3
Debt instruments, fair value	6,845.4	6,808.4
Notes Payable to Fumedica
Debt Instrument [Line Items]
Notes payable, fair value	6.3	6.1
Notes payable, carrying value	6.3	6.0
6.875% Senior Notes due 2018
Debt Instrument [Line Items]
Notes payable, fair value	575.7	583.7
Notes payable, carrying value	556.7	558.5
2.900% Senior Notes due 2020
Debt Instrument [Line Items]
Notes payable, fair value	1,528.1	1,521.5
Notes payable, carrying value	1,483.2	1,485.3
3.625% Senior Notes due 2022
Debt Instrument [Line Items]
Notes payable, fair value	1,032.4	1,026.6
Notes payable, carrying value	993.5	993.2
4.050% Senior Notes due 2025
Debt Instrument [Line Items]
Notes payable, fair value	1,812.9	1,796.0
Notes payable, carrying value	1,735.2	1,734.8
5.200% Senior Notes due 2045
Debt Instrument [Line Items]
Notes payable, fair value	1,890.0	1,874.5
Notes payable, carrying value	$ 1,721.6	$ 1,721.5