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Collaborative Arrangements - Eisai Co., Ltd. - Narrative (Details) - Alliance revenue - Lenvima - USD ($) | 9 Months Ended |
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Sep. 30, 2024 | Sep. 30, 2025
Licenses and Other |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |
Finite-lived intangible assets |  | $ 261,000,000
Eisai | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |
Sales based milestone payments | $ 125,000,000 |
Sales milestone payments |  | 2,300,000,000
Aggregate, regulatory milestones payments, maximum |  | $ 0

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