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Fair Value Measurements (Details Textual) SFr in Millions, $ in Millions | 6 Months Ended |  |
--- | --- | --- | ---
Jun. 30, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2006 CHF (SFr)
Business Acquisition, Contingent Consideration [Line Items] |  |  |
Asset impairment charges | $ 0.0 |  |
Fair value measurements, changes in valuation inputs | 0 |  |
Notes payable | $ 5,928.4 | $ 5,938.2 |
Contingent consideration obligations | 270.5 | 279.0 |
Notes Payable To Fumedica |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |
Notes payable | $ 0.0 | 3.2 | SFr 61.4
2.900% Senior Notes due 2020 |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |
Senior Notes interest rate | 2.90% |  |
Notes payable | $ 1,474.3 | 1,482.4 |
3.625% Senior Notes due 2022 |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |
Senior Notes interest rate | 3.625% |  |
Notes payable | $ 994.9 | 994.3 |
4.050% Senior Notes due 2025 |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |
Senior Notes interest rate | 4.05% |  |
Notes payable | $ 1,737.0 | 1,736.3 |
5.200% Senior Notes due 2045 |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |
Senior Notes interest rate | 5.20% |  |
Notes payable | $ 1,722.2 | $ 1,722.0 |

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