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Collaboration Agreements, License Agreement and Revenues - Drug Product Revenue - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Deferred Revenue	$ 6,897				$ 6,897		$ 15,857
Drug product revenue recognized	29,806		$ 24,364		90,633	$ 62,793
Royalty Revenue [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Deferred Revenue	100				100
Drug Product Revenue [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized	1,093		8,648		8,687	(168)
Drug Product Revenue [Member] \| Europe [Member] \| Astellas Agreement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized	1,076		0		1,076	0
Drug Product Revenue [Member] \| Japan [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized		$ 9,800
Drug Product Revenue [Member] \| Japan [Member] \| Astellas Agreement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized	17		(1,974)		7,611	$ 2,056
Drug Product Revenue [Member] \| API Shipment [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized		(2,200)	$ (2,000)	$ 4,000
Bulk Drug Product [Member] \| Astellas Agreement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized					43,300
Bulk Drug Product [Member] \| Astra Zeneca Agreements [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized					11,200
Bulk Drug Product [Member] \| E U Supply And Astellas Agreement [Member] \| Europe [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Deferred Revenue	23,200				$ 23,200
Billed Contracts Receivable		$ 49,200
Burdened manufacturing costs	$ 1,000