Fair Value Measurements (Details 1) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Summary of fair and carrying value of debt instruments
Total fair value	$ 6,808.4	$ 6,645.9
Notes Payable to Fumedica
Summary of fair and carrying value of debt instruments
Notes payable, fair value	6.1	9.4
6.875% Senior Notes due 2018
Summary of fair and carrying value of debt instruments
Notes payable, fair value	583.7	602.6
2.90% Senior Notes due 2020
Summary of fair and carrying value of debt instruments
Notes payable, fair value	1,521.5	1,497.5
3.625% Senior Notes due 2022
Summary of fair and carrying value of debt instruments
Notes payable, fair value	1,026.6	1,014.2
4.05% Senior Notes due 2025
Summary of fair and carrying value of debt instruments
Notes payable, fair value	1,796.0	1,764.6
5.20% Senior Notes due 2045
Summary of fair and carrying value of debt instruments
Notes payable, fair value	$ 1,874.5	$ 1,757.6