Condensed Consolidating Financial Information of Guarantor Subsidiaries - CONDENSED CONSOLIDATING CASH FLOW INFORMATION (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	$ 1,247	$ 1,250
Net cash (used in) provided by investing activities	(522)	(876)
Net cash (used in) provided by financing activities	(651)	(318)
Effect of foreign exchange rates	12	(14)
Net increase in cash and cash equivalents	86	42
Cash and cash equivalents at beginning of period	179	158
Cash and cash equivalents at end of period	265	200
Parent
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	2	6
Net cash (used in) provided by investing activities	(2)	(6)
Net cash (used in) provided by financing activities	0	0
Effect of foreign exchange rates	0	0
Net increase in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	0	0
URNA
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	1,096	1,069
Net cash (used in) provided by investing activities	(522)	(793)
Net cash (used in) provided by financing activities	(584)	(280)
Effect of foreign exchange rates	0	0
Net increase in cash and cash equivalents	(10)	(4)
Cash and cash equivalents at beginning of period	18	8
Cash and cash equivalents at end of period	8	4
Guarantor Subsidiaries
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	(1)	1
Net cash (used in) provided by investing activities	0	0
Net cash (used in) provided by financing activities	1	(1)
Effect of foreign exchange rates	0	0
Net increase in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	0	0
Non Guarantor Subsidiaries - Foreign
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	84	144
Net cash (used in) provided by investing activities	2	(77)
Net cash (used in) provided by financing activities	(2)	(7)
Effect of foreign exchange rates	12	(14)
Net increase in cash and cash equivalents	96	46
Cash and cash equivalents at beginning of period	161	150
Cash and cash equivalents at end of period	257	196
Non Guarantor Subsidiaries - SPV
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	66	30
Net cash (used in) provided by investing activities	0	0
Net cash (used in) provided by financing activities	(66)	(30)
Effect of foreign exchange rates	0	0
Net increase in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	0	0
Eliminations
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	0	0
Net cash (used in) provided by investing activities	0	0
Net cash (used in) provided by financing activities	0	0
Effect of foreign exchange rates	0	0
Net increase in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	$ 0	$ 0

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 increase (decrease) from the effect of exchange rate changes on cash and cash equivalent balances held in foreign currencies.

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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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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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