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Basis of Presentation and Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Mar. 31, 2024	Dec. 31, 2023
Other Commitments [Line Items]
Impairment of intangible assets	$ 0	$ 0	$ 0	$ 0
Intangible assets, net	107,859		107,859			$ 65,490
Amortization of intangible assets			7,631	1,364
Neuren Pharmaceuticals Limited [Member] \| License Agreements [Member]
Other Commitments [Line Items]
Finite-Lived Intangible Assets, Amortization Expense, Remainder of 2024	4,700		4,700
Amortization of intangible assets	2,300	$ 1,400	7,600	$ 1,400
Finite-Lived Intangible Assets, Amortization Expense, Subsequent year	$ 9,400		$ 9,400
FDA Approval Of DAYBUE [Member] \| Neuren Pharmaceuticals Limited [Member] \| License Agreements [Member]
Other Commitments [Line Items]
Intangible assets, net					$ 119,600