PROPERTY AND EQUIPMENT - Composition of our Property and Equipment Balances (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 3,473	$ 2,890
Accumulated depreciation	(1,517)	(1,097)
Property and equipment, net	1,956	1,793
Land
Property, Plant and Equipment [Line Items]
Property and equipment, gross	591	601
Buildings and leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,275	1,052
Furniture and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,439	1,121
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 168	$ 116

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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