Related Party Transactions - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Related Party Transaction [Line Items]
Accounts receivable from related parties	$ 11,563		$ 12,088
Accrued liabilities to related party	19,594		63,886
Investment income (loss)	796	$ 320
Equity method investments	5,884		5,061
Astellas [Member]
Related Party Transaction [Line Items]
Drug product revenue from a related party	2,100	7,600
Due to related parties	78,700		63,900
Astellas [Member] \| Collaborative Arrangement [Member]
Related Party Transaction [Line Items]
Accounts receivable from related parties	1,600		1,500
Deferred Revenue	23,400		40,300
Astellas [Member] \| License and Development [Member] \| Collaborative Arrangement [Member]
Related Party Transaction [Line Items]
Revenue related to collaboration agreements	1,600	27,800
Falikang [Member]
Related Party Transaction [Line Items]
Accounts receivable from related parties	9,900		10,500
Investment income (loss)	800	300
Equity method investments	$ 5,900		$ 5,100
Percentage of outstanding shares owned	51.10%
Falikang [Member] \| Collaborative Arrangement [Member]
Related Party Transaction [Line Items]
Revenue related to collaboration agreements	$ 21,400	$ 16,200

Drug product revenue from related party.

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