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Collaboration Agreements, License Agreement and Revenues - Summary of Revenue Recognized Under the Collaboration Agreements - Additional Information 4 (Detail) - USD ($) | 3 Months Ended | 9 Months Ended
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Sep. 30, 2022 | Sep. 30, 2022
Europe [Member] |  |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |  |
Remainder of transaction price, variable consideration from estimated future co-development billing |  | $ 6,300,000
Europe [Member] | Astellas Agreement [Member] |  |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |  |
Changes in revenue from changes to estimated variable consideration | $ 0 |
U.S./RoW and China [Member] |  |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |  |
Remainder of transaction price, variable consideration from estimated future co-development billing |  | 13,400,000
Changes in revenue from changes to estimated variable consideration |  | $ 0

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