License and Collaboration Agreements - Summary of Research and Development Costs Related to Collaboration and License Agreements (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development costs	$ 187,402	$ 142,903
General and administrative expense	54,246	54,016
Collaboration and License Agreements \| Cullinan
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development costs	28,401	24,909
General and administrative expense	3,247	2,051
Collaboration and License Agreements \| Adimab
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development costs	0	0
Collaboration and License Agreements \| Pearl - Taiho
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development costs	$ 7,640	$ 9,549

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.

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