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Investments in Variable Interest Entities (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2022
Variable Interest Entity [Line Items] |  |  |
(Gain) loss on equity method investments | $ 0.0 | $ (3.3) |
Percentage of future development costs related to Eisai | 45.00% |  |
Deferred tax assets, unrecognized tax benefit | $ 85.0 |  |
Investment in biotechnology companies that are determined to be unconsolidated variable interest entities | $ 28.0 |  | $ 27.8
Neurimmune |  |  |
Variable Interest Entity [Line Items] |  |  |
Collaboration agreement term | 12 years |  |
Research and development costs, percentage | 100.00% |  |
Eisai |  |  |
Variable Interest Entity [Line Items] |  |  |
Percentage of future development costs related to Eisai |  | 45.00% |

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