GOODWILL AND INTANGIBLE ASSETS (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Goodwill, Balance at beginning of period			$ 6,032	$ 5,649	$ 5,649
Goodwill acquired during the period			2		383
Reclassification to assets held for sale			(47)		0
Goodwill, Balance at end of period	$ 5,987		5,987		6,032
Intangible assets, Cost	1,410		1,410		1,487
Intangible assets, Accumulated Amortization	(388)		(388)		(416)
Amortizing intangible assets, Net	1,022		1,022		1,071
Amortization expense	20	$ 25	41	$ 47
Remainder of 2015	39		39
Future Amortization Expense, 2016	71		71
Future Amortization Expense, 2017	67		67
Future Amortization Expense, 2018	63		63
Future Amortization Expense, 2019	62		62
Future Amortization Expense, 2020	62		62
Future Amortization Expense, Thereafter	413		413
Future Amortization Expense, Total	777		777
Intangible Assets Not Subject to Amortization - Tradenames [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Intangible assets, Cost	244		244		244
Amortizing intangible assets, Net	244		244		244
Intangible Assets Not Subject to Amortization - Other [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Intangible assets, Cost	1		1		1
Amortizing intangible assets, Net	1		$ 1		1
Customer-related intangibles [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Weighted Average Amortization Period			19 years
Intangible assets, Cost	923		$ 923		929
Intangible assets, Accumulated Amortization	(278)		(278)		(259)
Amortizing intangible assets, Net	645		$ 645		670
Noncompete Agreements [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Weighted Average Amortization Period			5 years
Intangible assets, Cost	6		$ 6		43
Intangible assets, Accumulated Amortization	(3)		(3)		(37)
Amortizing intangible assets, Net	3		$ 3		6
Technology [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Weighted Average Amortization Period			14 years
Intangible assets, Cost	117		$ 117		118
Intangible assets, Accumulated Amortization	(43)		(43)		(38)
Amortizing intangible assets, Net	74		$ 74		80
Other [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Weighted Average Amortization Period			8 years
Intangible assets, Cost	119		$ 119		152
Intangible assets, Accumulated Amortization	(64)		(64)		(82)
Amortizing intangible assets, Net	55		$ 55		70
Total Amortizing Intangible Assets [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Weighted Average Amortization Period			17 years
Intangible assets, Cost	1,165		$ 1,165		1,242
Intangible assets, Accumulated Amortization	(388)		(388)		(416)
Amortizing intangible assets, Net	777		777		826
Noncompete Agreements, Fully Amortized [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Intangible assets, Cost	37		37
Intangible assets, Accumulated Amortization	$ (37)		$ (37)
Solstas, Summit Health, and Steward [Member]
Finite-Lived and Indefinite-lived Intangible Assets [Line Items]
Intangible assets					$ 270