Property and Equipment, net - Property and Equipment, net (Detail) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Property and equipment, gross		$ 4,989	$ 1,835
Less accumulated depreciation and amortization		(1,667)	(1,409)
Property and equipment, net	$ 3,417	3,322	426
Computer and Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross		239	239
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross		596	330
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross		$ 4,154	$ 1,266

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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