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Collaborative and Other Relationships - Summary of Activity Related To Denali Therapeutics (Details) - Research and development - Denali Therapeutics - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2024 | Mar. 31, 2023
Collaborative arrangements and non-collaborative arrangement transactions |  |
Expense incurred by the collaboration | $ 14.2 | $ 16.6
Expense reflected within statements of income | $ 8.5 | $ 10.0

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