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Collaboration Agreements, License Agreement and Revenues - Drug Product Revenue - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended			12 Months Ended
	Mar. 31, 2025	Dec. 31, 2024	Mar. 31, 2024	Dec. 31, 2024
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Deferred Revenue	$ 22,509	$ 27,290		$ 27,290
Drug product revenue recognized	2,739		$ 25,364
Other long-term liabilities	830	822		822
Astra Zeneca Agreements [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized	36,900		27,100
Drug Product Revenue, Net [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized	2,595		24,486
Drug Product Revenue, Net [Member] \| Astellas Agreement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized	2,600		(1,200)
Drug Product Revenue, Net [Member] \| Europe [Member] \| Astellas Agreement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized	814		1,021
Drug Product Revenue, Net [Member] \| Europe [Member] \| Astellas Europe Agreement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized	2,100
Burdened manufacturing costs		600
Drug Product Revenue, Net [Member] \| Japan [Member] \| Astellas Agreement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized	1,781		(2,205)
Accrued liabilities	700	2,500		2,500
Other long-term liabilities	600	600		600
Drug Product Revenue, Net [Member] \| API Shipment [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized	1,800		2,200
Bulk Drug Product [Member] \| Astellas Europe Agreement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Deferred Revenue		4,400		4,400
Bulk Drug Product [Member] \| Europe [Member] \| Astellas Europe Agreement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Drug product revenue recognized				7,200
Accrued liabilities	12,600	$ 10,500		$ 10,500
Bulk Drug Product [Member] \| Europe [Member] \| Astellas Europe Agreement [Member] \| Royalty Revenue [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Royalty revenue recognized as drug product revenue	$ 800		$ 1,000