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Collaboration, License, and Other Agreements - Amounts Recognized in Statement of Operations with Teva (Details) - Teva - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Reimbursement of research and development expenses |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Reduction of Research and development expense | $ 25.9 | $ 34.2 | $ 82.1 | $ 102.9
Amounts recognized in connection with up-front and development milestone payments received |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Other operating income | $ 17.2 | $ 22.8 | $ 54.5 | $ 68.8

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