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Fair Value Measurements (Details 1) - USD ($) $ in Millions | Dec. 31, 2016 | Dec. 31, 2015
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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

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