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Kyowa Kirin Collaboration and License Agreement - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Kyowa Kirin Collaboration and License Agreement [Line Items]
Current contract liabilities	$ 55,481,000		$ 55,481,000		$ 48,983,000
Long-term contract liabilities	398,604,000		398,604,000		$ 424,909,000
Collaboration revenue	20,874,000	$ 15,288,000	39,139,000	$ 29,396,000
Collaboration revenue
Kyowa Kirin Collaboration and License Agreement [Line Items]
Collaboration revenue	11,752,000	$ 15,288,000	24,251,000	29,396,000
Kyowa License Agreement
Kyowa Kirin Collaboration and License Agreement [Line Items]
Total transaction price upfront and milestone payments in aggregate including profit and loss and expense sharing			597,100,000
Upfront and milestone payments				$ 570,000,000
Profit and loss and expense sharing			27,100,000
Remaining eligible amount to receive in development regulatory and commercial milestone payments			693,000,000
Other upfront payments and development, regulatory and commercial milestone payments			228,000,000
Contract liability	454,100,000		454,100,000
Current contract liabilities	55,500,000		55,500,000
Long-term contract liabilities	398,600,000		398,600,000
Kyowa License Agreement \| Maximum
Kyowa Kirin Collaboration and License Agreement [Line Items]
Upfront and milestone payments in aggregate			1,491,000,000
Kyowa License Agreement \| Development Services for Monotherapy
Kyowa Kirin Collaboration and License Agreement [Line Items]
Remaining unrecognized consideration allocated development services	20,900,000		20,900,000
Collaboration revenue	6,200,000		13,400,000
Kyowa License Agreement \| Development Services in Combination with Other Therapies
Kyowa Kirin Collaboration and License Agreement [Line Items]
Remaining unrecognized consideration allocated development services	156,400,000		156,400,000
Collaboration revenue	5,600,000		10,900,000
Kyowa License Agreement \| Commercialization Services
Kyowa Kirin Collaboration and License Agreement [Line Items]
Current contract liabilities	8,700,000		8,700,000
Long-term contract liabilities	268,100,000		268,100,000
Remaining unrecognized consideration allocated development services	$ 276,800,000		$ 276,800,000