PROPERTY AND EQUIPMENT - Components of Property and Equipment, net (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 95,174	$ 122,152
Less: accumulated depreciation	(68,337)	(81,754)
Property and equipment, net	26,837	40,398
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	31,203	52,335
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	26,115	30,211
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	5,565	10,572
Computer software purchased
Property, Plant and Equipment [Line Items]
Property and equipment, gross	8,566	8,415
Computer software developed for internal use
Property, Plant and Equipment [Line Items]
Property and equipment, gross	19,463	18,542
Fixed assets in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 4,262	$ 2,077

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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