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License and Collaboration Agreements - Summary of Research and Development Costs Related to Collaboration and License Agreements (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
License And Collaboration Agreements [Line Items]
Research and development costs	$ 44,437	$ 61,030	$ 86,560	$ 102,489
General and administrative expense	12,817	14,768	24,391	28,305
Collaboration Agreements | Cullinan [Member]
License And Collaboration Agreements [Line Items]
Research and development costs	6,618	7,772	12,428	13,390
General and administrative expense	1,005	592	1,671	1,064
Collaboration Agreements | Pearl - Taiho
License And Collaboration Agreements [Line Items]
Research and development costs	$ 652	$ 3,112	$ 1,474	$ 4,486

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License and collaboration agreements.

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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Amount of expense for research and development. Includes, but is not limited to, cost for computer software product to be sold, leased, or otherwise marketed and writeoff of research and development assets acquired in transaction other than business combination or joint venture formation or both. Excludes write-down of intangible asset acquired in business combination or from joint venture formation or both, used in research and development activity.

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