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v3.19.3.a.u2

Investments in Variable Interest Entities (Details) - USD ($) $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
May 31, 2018 | Oct. 31, 2017 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Variable Interest Entity [Line Items] |  |  |  |  |
Payment to Neurimmune |  |  | $ (4.3) | $ 36.4 | $ 134.1
Potential Future Milestone Payments Commitment To Third Party Approximately |  |  | 6,800.0 |  |
Investment in Variable Interest Entities (Textual) |  |  |  |  |
Investment in biotechnology companies that are determined to be unconsolidated variable interest entities |  |  | 22.7 | $ 28.7 |
Neurimmune |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Payment to Neurimmune | $ 50.0 | $ 150.0 |  |  |
Additional reduction in royalty rate payable on commercial sales | 5.00% |  |  |  |
Reduction in royalty rate payable on commercial sales |  | 15.00% |  |  |
Regulatory Milestones |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Potential Future Milestone Payments Commitment To Third Party Approximately |  |  | 1,400.0 |  |
Regulatory Milestones | Neurimmune |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Potential Future Milestone Payments Commitment To Third Party Approximately |  |  | 75.0 |  |
Regulatory Approval Milestone | Neurimmune |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Potential Future Milestone Payments Commitment To Third Party Approximately |  |  | $ 100.0 |  |

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- Definition Amount of cash outflow to a noncontrolling interest. Includes, but not limited to, reduction of noncontrolling interest ownership. Excludes dividends paid to the noncontrolling interest. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585 + Details
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