SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment	$ 489,976	$ 498,847
Less: accumulated depreciation and amortization	(281,553)	(270,546)
Net property and equipment	208,423	228,301
Furniture, fixtures, and equipment
Property, Plant and Equipment [Line Items]
Property and equipment	283,378	272,733
Buildings
Property, Plant and Equipment [Line Items]
Property and equipment	112,410	130,959
Corporate aircraft
Property, Plant and Equipment [Line Items]
Property and equipment	11,461	11,337
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment	61,539	58,929
Land
Property, Plant and Equipment [Line Items]
Property and equipment	20,146	23,648
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment	$ 1,042	$ 1,241

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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