GOODWILL AND OTHER INTANGIBLE ASSETS Balances and Changes in Carrying Amounts of Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 544	$ 527
Divestiture		(3)
Impairment	(105)	(7)
Translation	(15)	27
Goodwill, ending balance	424	544
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Cumulative goodwill impairment charges, January 1, 2018	127
Cumulative goodwill impairment charges, December 31, 2018	232	127
United States
Goodwill [Roll Forward]
Goodwill, beginning balance	192	202
Divestiture		(3)
Impairment	0	(7)
Translation	0	0
Goodwill, ending balance	192	192
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Cumulative goodwill impairment charges, January 1, 2018	24
Cumulative goodwill impairment charges, December 31, 2018	24	24
Canada
Goodwill [Roll Forward]
Goodwill, beginning balance	130	122
Divestiture		0
Impairment	0	0
Translation	(10)	8
Goodwill, ending balance	120	130
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Cumulative goodwill impairment charges, January 1, 2018	32
Cumulative goodwill impairment charges, December 31, 2018	32	32
Other businesses
Goodwill [Roll Forward]
Goodwill, beginning balance	222	203
Divestiture		0
Impairment	(105)	0
Translation	(5)	19
Goodwill, ending balance	112	222
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Cumulative goodwill impairment charges, January 1, 2018	71
Cumulative goodwill impairment charges, December 31, 2018	$ 176	$ 71

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
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of accumulated impairment loss for an asset representing 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 of loss from the write-down 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

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-Publisher FASB
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Section 45
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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

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