Agreements - Summary of Aggregate Amount Paid for the Assets Acquired (Parenthetical) (Detail) - USD ($) $ in Thousands	1 Months Ended		9 Months Ended
	Jan. 31, 2023		Sep. 30, 2023
U.S. Rights for FYCOMPA [Member]
Asset Acquisition [Line Items]
Transaction expenses	$ 5,870	[1]	$ 5,900

[1] As of September 30, 2023, the full $5.9 million was paid in cash.