PROPERTY, EQUIPMENT AND SOFTWARE, NET (Schedule of Property, Equipment and Software) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property, equipment and software, gross	$ 323,887	$ 295,845
Less accumulated depreciation	(218,399)	(184,896)
Property, equipment and software, net	105,488	110,949
Capitalized website and internal-use software development costs
Property, Plant and Equipment [Line Items]
Property, equipment and software, gross	164,488	140,886
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, equipment and software, gross	88,436	86,089
Computer equipment
Property, Plant and Equipment [Line Items]
Property, equipment and software, gross	46,049	43,626
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, equipment and software, gross	18,271	18,403
Telecommunication
Property, Plant and Equipment [Line Items]
Property, equipment and software, gross	4,956	5,154
Software
Property, Plant and Equipment [Line Items]
Property, equipment and software, gross	$ 1,687	$ 1,687

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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