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Basis of Presentation and Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Other Commitments [Line Items]
Impairment of intangible assets	$ 0	$ 0	$ 0	$ 0
Intangible assets, net	105,515		105,515		$ 65,490
Amortization of intangible assets			9,975	2,728
Neuren Pharmaceuticals Limited [Member] \| License Agreements [Member]
Other Commitments [Line Items]
Finite-Lived Intangible Assets, Amortization Expense, Remainder of 2024	2,300		2,300
Amortization of intangible assets	2,300	$ 1,400	10,000	$ 2,700
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		$ 119,600