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v3.19.3.a.u2

Fair Value Measurements (Details Textual) - USD ($) $ in Millions | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Feb. 28, 2015 | Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Mar. 31, 2012 | Dec. 31, 2010 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2015 | Feb. 12, 2015
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value measurements, changes in valuation techniques |  |  |  |  |  |  |  |  |  |  |  | no | 0 |  |  |
Payments |  |  |  |  |  |  |  |  |  |  |  | $ 0.0 | $ 101.5 |  |  |
Loss (gain) on fair value remeasurement of contingent consideration |  | $ (2.6) | $ 57.8 | $ 20.0 | $ (11.5) | $ (79.3) | $ 87.9 | $ (1.9) | $ 5.6 |  |  | 63.7 | 12.3 | $ (62.7) |  |
Maximum contingent consideration in the form of development and approval milestones |  | 735.0 |  |  |  |  |  |  |  |  |  | 735.0 |  |  |  |
Convergence Pharmaceuticals |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additions | $ 274.5 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration obligations |  | 244.6 |  |  |  | 246.6 |  |  |  |  |  | 244.6 | 246.6 |  |  |
Maximum contingent consideration in the form of development and approval milestones |  | 400.0 |  |  |  |  |  |  |  |  |  | 400.0 |  |  |  |
In-process research and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 424.6
Stromedix, Inc. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments |  |  |  |  |  |  |  |  |  |  |  |  | (81.5) |  |  |
Additions |  |  |  |  |  |  |  |  |  | $ 122.2 |  |  |  |  |  |
Contingent consideration obligations |  |  |  |  |  | 83.0 |  |  |  |  |  |  | 83.0 |  |  |
In-process research and development |  |  |  |  |  |  |  |  |  | $ 219.2 |  |  |  |  |  |
Biogen Idec International Neuroscience GmbH |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additions |  |  |  |  |  |  |  |  |  |  | $ 81.2 |  |  |  |  |
Contingent consideration obligations |  | 101.5 |  |  |  | 80.2 |  |  |  |  |  | 101.5 | 80.2 |  |  |
Maximum contingent consideration in the form of development and approval milestones |  | $ 335.0 |  |  |  |  |  |  |  |  |  | $ 335.0 |  |  |  |
2.90% Senior Notes due 2020 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate on senior notes |  | 2.90% |  |  |  |  |  |  |  |  |  | 2.90% |  |  | 2.90% |
3.625% Senior Notes due 2022 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate on senior notes |  | 3.625% |  |  |  |  |  |  |  |  |  | 3.625% |  |  | 3.625% |
4.05% Senior Notes due 2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate on senior notes |  | 4.05% |  |  |  |  |  |  |  |  |  | 4.05% |  |  | 4.05% |
5.20% Senior Notes due 2045 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate on senior notes |  | 5.20% |  |  |  |  |  |  |  |  |  | 5.20% |  |  | 5.20% |
Other long-term liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration obligations |  | $ 197.7 |  |  |  | $ 265.0 |  |  |  |  |  | $ 197.7 | $ 265.0 |  |  |
Accrued expenses and other | Convergence Pharmaceuticals |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration obligations |  | $ 148.5 |  |  |  |  |  |  |  |  |  | $ 148.5 |  |  |  |
Discount rate | Convergence Pharmaceuticals |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value measurement and measurement inputs, recurring and nonrecurring |  | 2.10% |  |  |  |  |  |  |  |  |  | 2.10% |  |  |  |
Discount rate | Biogen Idec International Neuroscience GmbH |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value measurement and measurement inputs, recurring and nonrecurring |  | 2.30% |  |  |  |  |  |  |  |  |  | 2.30% |  |  |  |
BG00011 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss (gain) on fair value remeasurement of contingent consideration |  |  | $ 61.2 |  |  |  |  |  |  |  |  |  |  |  |  |

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