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Collaborative and Other Relationships - Acorda (Details) - Acorda - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2020 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |
Expected additional milestone payments when certain sales threshold is met | $ 15.0 |  |  |
Foreign sales required to trigger milestone | $ 100.0 |  |  |
Expense reflected within statements of income |  | $ 46.1 | $ 46.6 | $ 44.5

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- Details
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