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Investments in Variable Interest Entities (Details) - USD ($) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2024 | Dec. 31, 2023
Variable Interest Entity [Line Items] |  |
Investment in biotechnology companies that are determined to be unconsolidated variable interest entities | $ 22.8 | $ 16.4
Neurimmune |  |
Variable Interest Entity [Line Items] |  |
Research and development costs, percentage | 100.00% |
Deconsolidation, gain (loss), amount | $ 3.0 |

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