GOODWILL AND OTHER INTANGIBLE ASSETS - Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Changes in the carrying amount of goodwill
Total	$ 6,970.0
Goodwill allocated to assets held for sale	59.0
Total	7,425.0	$ 6,970.0
Hospital operations and other
Changes in the carrying amount of goodwill
Goodwill	5,803.0	5,552.0	$ 5,642.0
Accumulated impairment losses	(2,430.0)	(2,430.0)	(2,430.0)
Total	3,122.0	3,212.0
Goodwill acquired during the year and purchase price adjustments		251.0	100.0
Goodwill allocated to assets held for sale	7.0		(190.0)
Total	3,373.0	3,122.0	3,212.0
Conifer
Changes in the carrying amount of goodwill
Goodwill	605.0	605.0	606.0
Total	605.0	606.0
Goodwill allocated to assets held for sale			(1.0)
Total	605.0	605.0	606.0
Ambulatory Care
Changes in the carrying amount of goodwill
Goodwill	3,447.0	3,243.0	95.0
Impact of foreign currency translation		(32.0)	(13.0)
Total	3,243.0	95.0
Goodwill acquired during the year and purchase price adjustments		236.0	3,161.0
Goodwill allocated to assets held for sale	(36.0)
Total	$ 3,447.0	$ 3,243.0	$ 95.0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount before tax, after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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