Research Collaboration and License Agreements - Summary of Sources of Revenue (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Research Collaboration And License Agreements [Line Items]
Revenue	$ 15.6	$ 188.8
Vepdegestrant
Research Collaboration And License Agreements [Line Items]
Revenue	14.4	189.9
Pfizer, Inc.
Research Collaboration And License Agreements [Line Items]
Revenue	$ 1.2	$ (1.1)

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details