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INCOME TAXES - Changes in Valuation Allowance (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Deferred Tax Asset, Valuation Allowance [Roll Forward]
Balance at beginning of period	$ (72)	$ (72)
Balance at end of period	(53)	(72)
Increases primarily related to foreign NOLs
Deferred Tax Asset, Valuation Allowance [Roll Forward]
Valuation allowance, increase (decrease)	(16)	(9)
Releases related to foreign NOLs
Deferred Tax Asset, Valuation Allowance [Roll Forward]
Valuation allowance, increase (decrease)	0	10
Foreign subsidiaries tax impacts due to divestiture
Deferred Tax Asset, Valuation Allowance [Roll Forward]
Valuation allowance, increase (decrease)	39	0
Other changes, net
Deferred Tax Asset, Valuation Allowance [Roll Forward]
Valuation allowance, increase (decrease)	(2)	0
Increase related to U.S. foreign tax credits
Deferred Tax Asset, Valuation Allowance [Roll Forward]
Valuation allowance, increase (decrease)	$ (2)	$ (1)

X

- Definition

Deferred Tax Asset, Valuation Allowance [Roll Forward]

+ References

No definition available.

+ Details

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- 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/disclosureRef
-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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- Definition

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

+ References

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

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