Collaborative and Other Relationships - Summary of Activity Related To Denali Therapeutics (Details) - Research and development - Denali Therapeutics - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Collaborative arrangements and non-collaborative arrangement transactions
Expense incurred by the collaboration	$ 14.9	$ 12.6	$ 44.5	$ 51.3
Expense reflected within statements of income	$ 8.9	$ 7.6	$ 26.7	$ 30.8

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 808
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479402/808-10-50-1

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