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Basis of Presentation and Significant Accounting Policies - Additional Information (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2025 USD ($) Segment	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)
Other Commitments [Line Items]
Impairment of intangible assets	$ 0	$ 0	$ 0	$ 0
Intangible assets, net	111,615		111,615		$ 119,782
Amortization of intangible assets			$ 8,167	9,975
Number of operating segements \| Segment			1
Neuren Pharmaceuticals Limited [Member] \| License Agreements [Member]
Other Commitments [Line Items]
Finite-Lived Intangible Assets, Amortization Expense, Remainder of 2024	2,700		$ 2,700
Amortization of intangible assets	2,700	$ 2,300	8,200	$ 10,000
Finite-Lived Intangible Assets, Amortization Expense, Subsequent year	10,900		10,900
FDA approval, Sales of DAYBUE and Sale of PRV [Member] \| Neuren Pharmaceuticals Limited [Member] \| License Agreements [Member]
Other Commitments [Line Items]
Intangible assets, net	$ 138,800		$ 138,800