Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, gross	$ 55,772	$ 53,336
Less: accumulated depreciation	(27,327)	(27,535)
Construction-in-progress		90
Property and equipment, net	28,445	25,891
Office equipment and furniture [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, gross	3,102	3,739
Equipment and machinery [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, gross	2,451	2,877
Leasehold improvements [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, gross	21,278	16,651
Property and plant [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, gross	27,829	28,922
Motor vehicles [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, gross	$ 1,112	$ 1,147

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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