INCOME TAXES - Uncertain Tax Positions and Interest and Penalties - Additional Disclosures (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes
Unrecognized tax benefits that would impact effective tax rate if recognized	$ 43	$ 30
Liability for uncertain tax positions	62	55	$ 53
Reasonably possible reduction in the liability for uncertain tax positions	8
Other non-current liabilities
Income Taxes
Liability for uncertain tax positions	59	54
Other non-current assets
Income Taxes
Liability for uncertain tax positions	$ 3	$ 1

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns, and the amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

No definition available.

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- Definition

Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (d)(3)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32718-109319

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- References

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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=SL6600010-109319

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