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Collaborative Research and License Agreements - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands | 1 Months Ended | 9 Months Ended
--- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Sep. 30, 2021 | Sep. 30, 2023 | Sep. 30, 2022
Research And Development Arrangement Contract To Perform For Others [Line Items] |  |  |  |  |
Common stock shares purchased | 7,840,909 | 3,802,144 |  |  |
Proceeds from issuance of common stock | $ 162,000 | $ 81,200 |  | $ 0 | $ 19,427
Collaboration receivable | $ 3,474 |  |  | 3,407 |
Incyte Agreement [Member] |  |  |  |  |
Research And Development Arrangement Contract To Perform For Others [Line Items] |  |  |  |  |
Common stock shares purchased |  | 1,421,523 |  |  |
Purchase price per share |  | $ 24.62 |  |  |
Proceeds from issuance of common stock |  | $ 35,000 |  |  |
Collaboration receivable |  |  |  | 6,600 |
Collaboration expense due to counterparty |  |  |  | $ 3,200 |
Incyte Agreement [Member] | Maximum [Member] |  |  |  |  |
Research And Development Arrangement Contract To Perform For Others [Line Items] |  |  |  |  |
Potential milestone payments to be made |  |  | $ 220,000 |  |
Commercialization milestones and tiered royalties |  |  | $ 230,000 |  |
Incyte Agreement [Member] | Non-Refundable Cash Payments [Member] |  |  |  |  |
Research And Development Arrangement Contract To Perform For Others [Line Items] |  |  |  |  |
Upfront milestone payable |  | $ 117,000 |  |  |
Global and U.S. [Member] | Incyte Agreement [Member] |  |  |  |  |
Research And Development Arrangement Contract To Perform For Others [Line Items] |  |  |  |  |
Development costs associated with clinical trials |  |  | 45.00% |  |
Global and U.S. [Member] | Incyte Agreement [Member] | Incyte Corporation [Member] |  |  |  |  |
Research And Development Arrangement Contract To Perform For Others [Line Items] |  |  |  |  |
Development costs associated with clinical trials |  |  | 55.00% |  |
Ex-U.S. Countries [Member] | Incyte Agreement [Member] |  |  |  |  |
Research And Development Arrangement Contract To Perform For Others [Line Items] |  |  |  |  |
Development costs associated with clinical trials |  |  | 100.00% |  |

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