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Collaboration Agreements, License Agreement and Revenues - Summary of Revenue Recognized Under the Collaboration Agreements - Additional Information 4 (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023
Japan [Member] |  |
Disaggregation of Revenue [Line Items] |  |
Transaction price, variable consideration from estimated future co-development billing | $ 0 |
Europe [Member] |  |
Disaggregation of Revenue [Line Items] |  |
Transaction price, variable consideration from estimated future co-development billing | 0 |
U.S./RoW and China [Member] |  |
Disaggregation of Revenue [Line Items] |  |
Changes in revenue from changes to estimated variable consideration | 0 |
Astellas Agreement [Member] | Japan [Member] |  |
Disaggregation of Revenue [Line Items] |  |
Changes in revenue from changes to estimated variable consideration | 0 |
Transaction price, variable consideration from estimated future co-development billing | 0 | $ 0
Astellas Agreement [Member] | Japan [Member] | Co Development Information Sharing And Committee Services [Member] |  |
Disaggregation of Revenue [Line Items] |  |
Total Consideration | 17,100,000 |
Astellas Agreement [Member] | Japan [Member] | License [Member] |  |
Disaggregation of Revenue [Line Items] |  |
Total Consideration | 100,300,000 |
Astellas Agreement [Member] | Europe [Member] |  |
Disaggregation of Revenue [Line Items] |  |
Changes in revenue from changes to estimated variable consideration | 0 |
Astellas Agreement [Member] | Europe [Member] | Co Development Information Sharing And Committee Services [Member] |  |
Disaggregation of Revenue [Line Items] |  |
Total Consideration | 288,100,000 |
Astellas Agreement [Member] | Europe [Member] | License [Member] |  |
Disaggregation of Revenue [Line Items] |  |
Total Consideration | 619,000,000 |
AstraZeneca Agreements [Member] | U.S./RoW and China [Member] | Co Development Information Sharing And Committee Services [Member] |  |
Disaggregation of Revenue [Line Items] |  |
Total Consideration | 625,500,000 |
AstraZeneca Agreements [Member] | U.S./RoW and China [Member] | Product [Member] |  |
Disaggregation of Revenue [Line Items] |  |
Cumulative Revenue | 354,800,000 |
AstraZeneca Agreements [Member] | U.S./RoW and China [Member] | License [Member] |  |
Disaggregation of Revenue [Line Items] |  |
Total Consideration | 344,500,000 |
AstraZeneca Agreements [Member] | U.S./RoW and China [Member] | China Performance Obligation [Member] |  |
Disaggregation of Revenue [Line Items] |  |
Total Consideration | $ 486,900,000 |

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