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Collaboration Agreements, License Agreement and Revenues - Drug Product Revenue - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Deferred Revenue	$ 7,361				$ 7,361		$ 15,857
Drug product revenue recognized	15,735			$ 155,973	106,367	$ 218,766
Royalty Revenue [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Royalty revenue recognized as drug product revenue	200				300
Astra Zeneca Agreements [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Royalty revenue recognized as drug product revenue					50,873
Drug Product Revenue [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized	4,077			0	4,610	(168)
Drug Product Revenue [Member] \| Europe [Member] \| Astellas Agreement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized	236			0	1,313	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	4,313			$ 0	3,297	2,056
Drug Product Revenue [Member] \| API Shipment [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized	(4,300)					$ 2,100
Drug Product Revenue [Member] \| API Shipment [Member] \| Japan [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized			2,200
Bulk Drug Product [Member] \| Astellas Agreement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized					51,000
Accrued liabilities	51,000				51,000
Bulk Drug Product [Member] \| Astra Zeneca Agreements [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized					11,200
Accrued liabilities	$ 11,200				$ 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
Billed Contracts Receivable			$ 49,200
Burdened manufacturing costs		$ 1,000