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In-Licensing Arrangement (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Mar. 31, 2023
In-Licensing arrangement [Line Items] |  |  |  |  |
Research and development | $ 40,791 | $ 51,732 | $ 80,489 | $ 97,760 |
Contractual Obligation | 4,800 |  | 4,800 |  |
Synaffix B.V. |  |  |  |  |
In-Licensing arrangement [Line Items] |  |  |  |  |
Potential development and regulatory milestone payments under agreement |  |  |  |  | $ 2,800,000
Research and development | $ 1,200 | $ 1,000 | $ 2,400 | $ 3,400 |

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