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Collaboration Agreements, License Agreement and Revenues - AstraZeneca Agreements - Additional Information 1 (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	Jul. 30, 2013	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Total revenue		$ 1,076	$ 123	$ 5,163	$ 26,486
AstraZeneca Agreements [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Total revenue		$ 165,300	$ 42,200	218,600	$ 115,300
AstraZeneca Agreements [Member] | U.S./RoW [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Aggregate considerations received				439,000
AstraZeneca Agreements [Member] | China [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront, non-contingent, non-refundable and time-based payments	$ 376,700
Aggregate considerations received				$ 81,200

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