v3.26.1

Kyowa Kirin Collaboration and License Agreement - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Kyowa Kirin Collaboration and License Agreement [Line Items]
Current contract liabilities	$ 47,704,000		$ 48,983,000
Long-term contract liabilities	416,745,000		$ 424,909,000
Collaboration revenue	18,265,000	$ 14,108,000
Collaboration revenue
Kyowa Kirin Collaboration and License Agreement [Line Items]
Collaboration revenue	12,499,000	$ 14,108,000
Kyowa License Agreement
Kyowa Kirin Collaboration and License Agreement [Line Items]
Total transaction price upfront and milestone payments in aggregate including profit and loss share	595,700,000
Upfront and milestone payments	570,000,000
Profit and loss sharing payments	25,700,000
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	464,400,000
Current contract liabilities	47,700,000
Long-term contract liabilities	416,700,000
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	27,000,000
Collaboration revenue	7,200,000
Kyowa License Agreement \| Development Services in Combination with Other Therapies
Kyowa Kirin Collaboration and License Agreement [Line Items]
Remaining unrecognized consideration allocated development services	161,700,000
Collaboration revenue	5,300,000
Kyowa License Agreement \| Commercialization Services
Kyowa Kirin Collaboration and License Agreement [Line Items]
Current contract liabilities	2,000,000
Long-term contract liabilities	273,700,000
Remaining unrecognized consideration allocated development services	$ 275,700,000

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Kura Oncology, Inc. 10-Q