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v3.19.3.a.u2

Commitments and Contingencies (Details Textual) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Apr. 02, 2013
Business Acquisition [Line Items] |  |  |  |  |
Maximum contingent consideration in the form of development and approval milestones |  | $ 735.0 |  |  |
Increase to goodwill |  | 117.5 | $ 1,080.1 |  |
Potential future milestone payments commitment, approximately |  | 6,800.0 |  |  |
Cancellable future commitments |  | 514.0 |  |  |
Income Taxes Paid |  | 87.0 |  |  |
Commitments And Contingencies (Textual) |  |  |  |  |
Accrued expenses |  | 24.0 |  |  |
Liabilities associated with uncertain tax positions |  | 136.9 |  |  |
TYSABRI |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Future contingent payment for annual worldwide net sales up to $2.0 billion |  |  |  |  | 18.00%
Future contingent payment threshold |  |  |  |  | $ 2,000.0
Future contingent payment for annual worldwide net sales that exceed $2.0 billion |  |  |  |  | 25.00%
Solothurn |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Cancellable future commitments |  | 52.0 |  |  |
TECFIDERA | Fumapharm AG |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Increase to goodwill | $ 300.0 |  | 1,200.0 |  |
Twenty billion | TECFIDERA | Fumapharm AG |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Cumulative sales level | 20,000.0 |  | 20,000.0 |  |
Increase to goodwill | 300.0 |  |  |  |
Each additional one billion up to twenty billion | TECFIDERA | Fumapharm AG |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Cumulative sales level | $ 20,000.0 |  | $ 20,000.0 |  |
Development Milestones |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Potential future milestone payments commitment, approximately |  | 1,200.0 |  |  |
Regulatory Milestones |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Potential future milestone payments commitment, approximately |  | 1,400.0 |  |  |
Commercial Milestones [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Potential future milestone payments commitment, approximately |  | 4,200.0 |  |  |
2017 Tax Act |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Transition toll tax liabilities |  | $ 697.0 |  | $ 989.6 |
Ionis Pharmaceuticals | Minimum | SPINRAZA |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Percentage Of Royalties As Per Collaboration |  | 11.00% |  |  |
Ionis Pharmaceuticals | Maximum | SPINRAZA |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Percentage Of Royalties As Per Collaboration |  | 15.00% |  |  |
Alkermes |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Potential future milestone payments commitment, approximately |  | $ 155.0 |  |  |
Alkermes | VUMERITY |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Percentage Of Royalties As Per Collaboration |  | 15.00% |  |  |
Twelve months |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Potential future milestone payments commitment, approximately |  | $ 430.0 |  |  |

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