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Fair Value Measurements (Details 1) - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Debt Instrument |  |
Total fair value | $ 6,483.3 | $ 6,808.4
Notes Payable to Fumedica |  |
Debt Instrument |  |
Notes payable, fair value | 3.2 | 6.1
6.875% Senior Notes due 2018 |  |
Debt Instrument |  |
Notes payable, fair value | 0.0 | 583.7
2.90% Senior Notes due 2020 |  |
Debt Instrument |  |
Notes payable, fair value | 1,517.7 | 1,521.5
3.625% Senior Notes due 2022 |  |
Debt Instrument |  |
Notes payable, fair value | 1,032.9 | 1,026.6
4.05% Senior Notes due 2025 |  |
Debt Instrument |  |
Notes payable, fair value | 1,851.9 | 1,796.0
5.20% Senior Notes due 2045 |  |
Debt Instrument |  |
Notes payable, fair value | $ 2,077.6 | $ 1,874.5

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