PROPERTY AND EQUIPMENT (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Property and equipment
Property and equipment, gross	$ 1,688	$ 1,558
Less: accumulated depreciation	(865)	(793)
Total property and equipment, net	823	765
Land and improvements
Property and equipment
Property and equipment, gross	74	75
Real estate held for development and sale
Property and equipment
Property and equipment, gross	25	26
Buildings and improvements
Property and equipment
Property and equipment, gross	$ 307	293
Buildings and improvements \| Minimum
Property and equipment
Estimated useful lives	10 years
Buildings and improvements \| Maximum
Property and equipment
Estimated useful lives	30 years
Operating equipment
Property and equipment
Property and equipment, gross	$ 939	781
Operating equipment \| Minimum
Property and equipment
Estimated useful lives	5 years
Operating equipment \| Maximum
Property and equipment
Estimated useful lives	10 years
Office furniture and equipment
Property and equipment
Property and equipment, gross	$ 123	114
Office furniture and equipment \| Minimum
Property and equipment
Estimated useful lives	5 years
Office furniture and equipment \| Maximum
Property and equipment
Estimated useful lives	10 years
Leasehold improvements
Property and equipment
Property and equipment, gross	$ 59	36
Leasehold improvements \| Minimum
Property and equipment
Estimated useful lives	10 years
Leasehold improvements \| Maximum
Property and equipment
Estimated useful lives	30 years
Automotive equipment
Property and equipment
Property and equipment, gross	$ 66	64
Automotive equipment \| Minimum
Property and equipment
Estimated useful lives	3 years
Automotive equipment \| Maximum
Property and equipment
Estimated useful lives	5 years
Finance lease assets
Property and equipment
Property and equipment, gross	$ 59	53
Construction in progress
Property and equipment
Property and equipment, gross	$ 36	$ 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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