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Fair Value Measurements (Details Textual) - USD ($) $ in Millions | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | ---
Feb. 28, 2015 | Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2015 | Sep. 30, 2014 | Feb. 12, 2015 | Dec. 31, 2014
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |
Asset impairment charges |  |  |  | $ 0.0 |  |  |
Changes in valuation techniques |  |  |  | 0 |  |  |
Reclassification of debt issuance costs |  | $ 47.5 |  |  |  |  |
Contingent consideration obligations |  | 301.9 |  | $ 301.9 |  |  | $ 200.0
Contingent consideration |  | 0.0 | $ 0.0 | 274.5 | $ 0.0 |  |
Current portion of contingent consideration obligations |  | 479.5 |  | 479.5 |  |  | $ 265.5
Convergence Pharmaceuticals |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |
Contingent consideration | $ 274.5 |  |  |  |  |  |
Potential future milestone payments |  |  |  |  |  | $ 450.0 |
Discount rate | 2.00% |  |  |  |  |  |
Current portion of contingent consideration obligations |  | $ 176.4 |  | $ 176.4 |  |  |
In-process research and development and other intangible assets |  |  |  |  |  | $ 424.6 |
6.875% Senior Notes due 2018 |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |
Senior Notes interest rate |  | 6.875% |  | 6.875% |  |  |
2.900% Senior Notes due 2020 |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |
Senior Notes interest rate |  | 2.90% |  | 2.90% |  |  |
3.625% Senior Notes due 2022 |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |
Senior Notes interest rate |  | 3.625% |  | 3.625% |  |  |
4.050% Senior Notes due 2025 |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |
Senior Notes interest rate |  | 4.05% |  | 4.05% |  |  |
5.200% Senior Notes due 2045 |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |
Senior Notes interest rate |  | 5.20% |  | 5.20% |  |  |
Adjustment for new accounting principle, early adoption | 6.875% Senior Notes due 2018 |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |
Reclassification of debt issuance costs |  | $ 1.8 |  |  |  |  |

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