Agreements - Summary of Total Purchase Price Allocated to Acquired Assets (Detail) - USD ($) $ in Thousands	1 Months Ended
	Jul. 31, 2023	Jan. 31, 2023
Asset Acquisition [Line Items]
Total purchase consideration	$ 94,978
U.S. Rights for FYCOMPA [Member]
Asset Acquisition [Line Items]
Inventory		$ 4,100
Prepaid expenses and other current assets (samples)		130
Prepaid commercialization expenses		1,576
Property and equipment, net		433
License and acquired intangibles for FYCOMPA®		158,143
Accrued preclinical and clinical trial expenses		(174)
Total purchase consideration		$ 164,208