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Collaborative and Other Relationships - Summary of Activity Related To Denali Therapeutics (Details) - Research and development - Denali Therapeutics - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Collaborative arrangements and non-collaborative arrangement transactions |  |  |
Expense incurred by the collaboration | $ 75.1 | $ 42.5 | $ 14.6
Expense reflected within statements of income | $ 43.8 | $ 25.5 | $ 8.8

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