Property, Plant and Equipment, Net - Schedule of Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Total	$ 31,364	$ 31,749	$ 32,357	$ 35,357	$ 34,752
Less: accumulated depreciation	(11,716)	(11,316)	(10,771)	(9,961)	(8,335)
Less: Impairment	(3,457)	0	0	0	0
Deposit for fixed assets	65	14	132	79	0
Construction in process	0	0	0	0	151
Net book value	16,256	20,447	21,718	25,475	26,568
Land
Property, Plant and Equipment [Line Items]
Total	329	334	340	371	363
Buildings
Property, Plant and Equipment [Line Items]
Total	24,248	24,625	25,050	27,327	26,740
Machinery and equipment
Property, Plant and Equipment [Line Items]
Total	778	735	748	798	643
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total	5,724	5,766	5,865	6,479	6,456
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Total	235	239	243	266	272
Motor vehicle
Property, Plant and Equipment [Line Items]
Total	$ 50	$ 50	$ 111	$ 116	$ 278

Deposits made for acquisition of property plant and equipment.

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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 of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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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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