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Basis of Presentation and Significant Accounting Policies - Additional Information (Detail) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) Segment	Jun. 30, 2024 USD ($)	Mar. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Other Commitments [Line Items]
Impairment of intangible assets	$ 0	$ 0	$ 0	$ 0
Intangible assets, net	114,338		114,338			$ 119,782
Amortization of intangible assets			$ 5,444	7,631
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					$ 5,400
Amortization of intangible assets	2,700	$ 2,300	$ 5,400	$ 7,600
Finite-Lived Intangible Assets, Amortization Expense, Subsequent year					$ 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