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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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