Research, Collaboration and Licensing Agreements - Schedule Of Collaborative Arrangements and Noncollaborative Arrangement Transactions (Detail) - USD ($) $ in Thousands	1 Months Ended			12 Months Ended
	Dec. 31, 2021	Nov. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 12)				$ 26,680	$ 38,951	$ 29,544
Research support payments and other payments
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 12)				5,680	7,951	4,014
Bei Gene
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 12)				0	0	3,530
Bei Gene | Milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 12)	$ 8,000	$ 10,000	$ 5,000	8,000	15,000	0
Janssen Biotech, Inc.
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 12)					0	0
Iconic Therapeutics Inc | Milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 12)				0	0	1,000
Iconic Therapeutics Inc | Partner Revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 12)				5,000	4,000	0
BMS
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 12)				0	12,000	0
BMS | Option Exercise Fee
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 12)				0	0	7,500
Merck Sharp and Dohme Research Ltd. | Milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 12)				0	0	2,000
Eli Lilly and Company | Milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 12)				0	0	8,000
Daiichi Sankyo, Co., Ltd | Commercial License Option Exercise
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 12)				$ 0	$ 0	$ 3,500