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Collaboration and License Agreements - Astellas Pharma Inc - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended				6 Months Ended
	Mar. 23, 2020	Jun. 30, 2026	Mar. 31, 2026	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025	Dec. 31, 2024
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue		$ 1,418		$ 18,658		$ 11,677	$ 69,575
Deferred revenue		54,690		32,291		54,690	32,291	$ 28,467	$ 94,063
Astellas Pharma Inc.
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue		79		$ 4,646		$ 9,072	$ 14,093
Collaboration and License Agreement | Astellas Pharma Inc.
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment received	$ 80,000
Milestone payments received					$ 5,000
Revenue			$ 7,100
Deferred revenue								8,600
Investment income (loss) per share						$ (0.04)
Amount due from customer		$ 30				$ 30		$ 900

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