PROPERTY AND EQUIPMENT (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 243,290	$ 193,094
Accumulated depreciation and amortization	(135,761)	(109,791)
Property and equipment, net	107,529	83,303
Depreciation expense for property and equipment	26,000	26,000	$ 26,000
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	73,918	65,332
Furniture, Office Equipment and Vehicles
Property, Plant and Equipment [Line Items]
Property and equipment, gross	60,768	50,224
Computer Hardware and Software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	80,947	74,742
Aircraft
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 27,657	$ 2,796

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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