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INCOME TAXES - Changes in Valuation Allowance (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Deferred Tax Asset, Valuation Allowance [Roll Forward]
Balance at beginning of period	$ (84)	$ (73)
Balance at end of period	(72)	(84)
Valuation allowance increases primarily related to foreign NOLs [Member]
Deferred Tax Asset, Valuation Allowance [Roll Forward]
Valuation allowance, increase (decrease)	(3)	(13)
Valuation allowance releases related to foreign NOLs [Member]
Deferred Tax Asset, Valuation Allowance [Roll Forward]
Valuation allowance, increase (decrease)	16	8
Other valuation allowance changes, net [Member]
Deferred Tax Asset, Valuation Allowance [Roll Forward]
Valuation allowance, increase (decrease)	0	5
Valuation allowance increase related to U.S. foreign tax credits [Member]
Deferred Tax Asset, Valuation Allowance [Roll Forward]
Valuation allowance, increase (decrease)	$ (1)	$ (11)

X

- Definition

Deferred Tax Asset, Valuation Allowance [Roll Forward]

+ References

No definition available.

+ Details

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X

- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

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X

- Definition

Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=84176650&loc=d3e32123-109318

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