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Fair Value Measurements (Details 1) - USD ($) $ in Millions | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | ---
Summary of fair and carrying value of debt instruments |  |
Total fair value | $ 6,645.9 | $ 647.2
Notes Payable to Fumedica |  |
Summary of fair and carrying value of debt instruments |  |
Notes payable, fair value | 9.4 | 12.6
6.875% Senior Notes due 2018 |  |
Summary of fair and carrying value of debt instruments |  |
Notes payable, fair value | 602.6 | 634.6
2.90% Senior Notes due 2020 |  |
Summary of fair and carrying value of debt instruments |  |
Notes payable, fair value | 1,497.5 | 0.0
3.625% Senior Notes due 2022 |  |
Summary of fair and carrying value of debt instruments |  |
Notes payable, fair value | 1,014.2 | 0.0
4.05% Senior Notes due 2025 |  |
Summary of fair and carrying value of debt instruments |  |
Notes payable, fair value | 1,764.6 | 0.0
5.20% Senior Notes due 2045 |  |
Summary of fair and carrying value of debt instruments |  |
Notes payable, fair value | $ 1,757.6 | $ 0.0

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