Condensed Consolidating Financial Information of Guarantor Subsidiaries - CONDENSED CONSOLIDATING CASH FLOW INFORMATION (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	$ 1,337	$ 1,247
Net cash (used in) provided by investing activities	(1,692)	(522)
Net cash provided by (used in) financing activities	370	(651)
Effect of foreign exchange rates	11	12
Net (decrease) increase in cash and cash equivalents	26	86
Cash and cash equivalents at beginning of period	312	179
Cash and cash equivalents at end of period	338	265
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 provided by (used in) financing activities	0	0
Effect of foreign exchange rates	0	0
Net (decrease) 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
Parent \| Reportable Legal Entities
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	10	2
Net cash (used in) provided by investing activities	(10)	(2)
Net cash provided by (used in) financing activities	0	0
Effect of foreign exchange rates	0	0
Net (decrease) 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 \| Reportable Legal Entities
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	1,305	1,096
Net cash (used in) provided by investing activities	(1,632)	(522)
Net cash provided by (used in) financing activities	315	(584)
Effect of foreign exchange rates	0	0
Net (decrease) increase in cash and cash equivalents	(12)	(10)
Cash and cash equivalents at beginning of period	21	18
Cash and cash equivalents at end of period	9	8
Guarantor Subsidiaries \| Reportable Legal Entities
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 provided by (used in) financing activities	1	1
Effect of foreign exchange rates	0	0
Net (decrease) 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 \| Reportable Legal Entities
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	78	84
Net cash (used in) provided by investing activities	(50)	2
Net cash provided by (used in) financing activities	(1)	(2)
Effect of foreign exchange rates	11	12
Net (decrease) increase in cash and cash equivalents	38	96
Cash and cash equivalents at beginning of period	291	161
Cash and cash equivalents at end of period	329	257
Non-Guarantor Subsidiaries - SPV \| Reportable Legal Entities
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	(55)	66
Net cash (used in) provided by investing activities	0	0
Net cash provided by (used in) financing activities	55	(66)
Effect of foreign exchange rates	0	0
Net (decrease) 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
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (a)
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-Name Accounting Standards Codification
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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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