PROPERTY AND EQUIPMENT, NET - Details of property and equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 197,878	$ 195,094
Less: Accumulated depreciation	(85,036)	(80,363)
Property and equipment, net	112,842	114,731
Buildings and Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	2,187	1,776
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	115,496	115,404
Computer and Communication Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	27,472	26,623
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	4,384	4,352
Vehicles [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	261	262
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	42,331	42,984
Construction in Process [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 5,747	$ 3,693

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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