PROPERTY AND EQUIPMENT, NET (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 344,481		$ 327,723
Less: Accumulated depreciation and amortization	(193,822)		(178,529)
Property and equipment, net	150,659		149,194
Depreciation and amortization expense	15,900	$ 15,500
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	116,407		111,942
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	111,010		106,469
Capitalized software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	89,218		81,984
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 27,846		$ 27,328

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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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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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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