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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
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Mar. 31, 2021 | Mar. 31, 2020
Reimbursement of research and development expenses | Research and development expense |  |
Disaggregation of Revenue [Line Items] |  |
Reduction of Research and development expense | $ 19.8 | $ 25.2
Amounts recognized in connection with up-front and development milestone payments received | Other operating income |  |
Disaggregation of Revenue [Line Items] |  |
Other operating income | $ 12.2 | $ 16.6

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