Condensed Consolidating Financial Information of Guarantor Subsidiaries - CONDENSED CONSOLIDATING CASH FLOW INFORMATION (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	$ 1,557	$ 1,466
Net cash used in investing activities	(1,192)	(1,906)
Net cash (used in) provided by financing activities	(328)	441
Effect of foreign exchange rates	(24)	(8)
Net increase (decrease) in cash and cash equivalents	13	(7)
Cash and cash equivalents at beginning of period	158	175
Cash and cash equivalents at end of period	171	168
Parent
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	9	11
Net cash used in investing activities	(9)	(11)
Net cash (used in) provided by financing activities	0	0
Effect of foreign exchange rates	0	0
Net increase (decrease) 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	1,440	1,369
Net cash used in investing activities	(1,062)	(1,696)
Net cash (used in) provided by financing activities	(370)	349
Effect of foreign exchange rates	0	0
Net increase (decrease) in cash and cash equivalents	8	22
Cash and cash equivalents at beginning of period	8	17
Cash and cash equivalents at end of period	16	39
Guarantor Subsidiaries
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	(2)	3
Net cash used in investing activities	0	0
Net cash (used in) provided by financing activities	2	(3)
Effect of foreign exchange rates	0	0
Net increase (decrease) 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	157	180
Net cash used in investing activities	(121)	(199)
Net cash (used in) provided by financing activities	(7)	(2)
Effect of foreign exchange rates	(24)	(8)
Net increase (decrease) in cash and cash equivalents	5	(29)
Cash and cash equivalents at beginning of period	150	158
Cash and cash equivalents at end of period	155	129
Non Guarantor Subsidiaries - SPV
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	(47)	(97)
Net cash used in investing activities	0	0
Net cash (used in) provided by financing activities	47	97
Effect of foreign exchange rates	0	0
Net increase (decrease) 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 investing activities	0	0
Net cash (used in) provided by financing activities	0	0
Effect of foreign exchange rates	0	0
Net increase (decrease) 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.

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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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