CONDENSED CONSOLIDATING FINANCIAL INFORMATION - Statement of Cash Flows (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Net cash (used) provided by operating activities	$ 225	$ 145
Net cash used by investing activities	(174)	(31)
Net cash provided (used) by financing activities	(35)	(116)
Increase (decrease) in cash and cash equivalents	16	(2)
Cash and cash equivalents-beginning of period	12	12
Cash and cash equivalents-end of period	28	10
Parent \| Reportable Legal Entity
Net cash (used) provided by operating activities	(403)	(419)
Net cash used by investing activities	(2)	(1)
Net cash provided (used) by financing activities	409	420
Increase (decrease) in cash and cash equivalents	4
Cash and cash equivalents-end of period	4
Combined Guarantor Subsidiaries \| Reportable Legal Entity
Net cash (used) provided by operating activities	621	563
Net cash used by investing activities	(90)	(30)
Net cash provided (used) by financing activities	(536)	(535)
Increase (decrease) in cash and cash equivalents	(5)	(2)
Cash and cash equivalents-beginning of period	12	12
Cash and cash equivalents-end of period	7	10
Combined Non-Guarantor Subsidiaries \| Reportable Legal Entity
Net cash (used) provided by operating activities	7	1
Net cash used by investing activities	(82)
Net cash provided (used) by financing activities	92	$ (1)
Increase (decrease) in cash and cash equivalents	17
Cash and cash equivalents-end of period	$ 17

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6676-107765

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3044-108585

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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