Property and Equipment, Net - Components of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 3,620	$ 3,620
Less: Accumulated depreciation and amortization	(3,620)	(3,618)
Property and equipment, net	0	2
Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,636	1,636
Manufacturing Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,338	1,338
Computer Software and Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	437	437
Office Furniture and Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 209	$ 209