GOODWILL AND INTANGIBLE ASSETS (Schedules) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Roll Forward]
Goodwill, balance at beginning of year	$ 6,000	$ 5,905
Goodwill acquired during the year	335	95	$ 33
Goodwill, balance at end of year	6,335	6,000	$ 5,905
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Intangible assets, gross excluding goodwill	1,653	1,409
Accumulated amortization, intangible assets	(534)	(460)
Total intangible assets, net	1,119	949
Future amortization expense, 2018	82
Future amortization expense, 2019	81
Future amortization expense, 2020	81
Future amortization expense, 2021	74
Future amortization expense, 2022	72
Future amortization expense, thereafter	493
Future amortization expense, total	883
Intangible Assets Not Subject to Amortization - Tradenames [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Intangible assets, gross excluding goodwill	235	235
Total intangible assets, net	235	235
Intangible Assets Not Subject to Amortization - Other [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Intangible assets, gross excluding goodwill	1	1
Total intangible assets, net	$ 1	1
Customer Relationships [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Weighted average amortization period	18 years
Intangible assets, gross excluding goodwill	$ 1,210	971
Accumulated amortization, intangible assets	(404)	(346)
Total intangible assets, net	$ 806	625
Non-compete Agreements [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Weighted average amortization period	7 years
Intangible assets, gross excluding goodwill	$ 7	6
Accumulated amortization, intangible assets	(5)	(4)
Total intangible assets, net	$ 2	2
Technology [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Weighted average amortization period	17 years
Intangible assets, gross excluding goodwill	$ 95	93
Accumulated amortization, intangible assets	(45)	(40)
Total intangible assets, net	$ 50	53
Other Intangible Assets, Subject To Amortization [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Weighted average amortization period	10 years
Intangible assets, gross excluding goodwill	$ 105	103
Accumulated amortization, intangible assets	(80)	(70)
Total intangible assets, net	$ 25	33
Total Amortizing Intangible Assets [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Weighted average amortization period	17 years
Intangible assets, gross excluding goodwill	$ 1,417	1,173
Accumulated amortization, intangible assets	(534)	(460)
Total intangible assets, net	$ 883	$ 713