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License and Collaboration Agreements - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2025	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 Cost		12,817	14,768	$ 24,391	28,305
Genrix License Agreement | Research and Development
License And Collaboration Agreements [Line Items]
Upfront license fee	$ 20,000
Pearl - Taiho
License And Collaboration Agreements [Line Items]
Percentage of profits from potential sales				50.00%
Percentage of Independent Development Costs				50.00%
RecievablesFromRelatedParty		130,000		$ 130,000
Pearl - Taiho | Collaboration Agreements
License And Collaboration Agreements [Line Items]
Research and development costs		652	3,112	1,474	4,486
Genrix Biopharmaceutical Co, Ltd | Genrix License Agreement
License And Collaboration Agreements [Line Items]
Upfront license fee				20,000
Genrix Biopharmaceutical Co, Ltd | Maximum | Genrix License Agreement
License And Collaboration Agreements [Line Items]
Milestone payments				292,000
Genrix Biopharmaceutical Co, Ltd | Maximum | Genrix License Agreement | Sales Based [Member]
License And Collaboration Agreements [Line Items]
Milestone payments				400,000
Cullinan [Member] | Collaboration Agreements
License And Collaboration Agreements [Line Items]
Research and development costs		6,618	7,772	12,428	13,390
General and administrative Cost		$ 1,005	$ 592	$ 1,671	$ 1,064

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