Consolidating Guarantor Financial Information Condensed Cash Flow Statement (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Condensed Financial Statements, Captions [Line Items]
Cash flows from operating activities	$ 122	$ 187
Cash flows from investing activities	(523)	(454)
Cash flows from financing activities	436	261
Change in cash	35	(6)
Cash and cash equivalents at beginning of period	24	19
Cash and cash equivalents at end of period	59	13
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Cash flows from operating activities	0	0
Cash flows from investing activities	0	0
Cash flows from financing activities	0	0
Change in cash	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	0	0
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash flows from operating activities	108	168
Cash flows from investing activities	(449)	(451)
Cash flows from financing activities	341	283
Change in cash	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 [Member]
Condensed Financial Statements, Captions [Line Items]
Cash flows from operating activities	8	18
Cash flows from investing activities	(100)	(3)
Cash flows from financing activities	126	(21)
Change in cash	34	(6)
Cash and cash equivalents at beginning of period	32	19
Cash and cash equivalents at end of period	66	13
Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Cash flows from operating activities	6	1
Cash flows from investing activities	26	0
Cash flows from financing activities	(31)	(1)
Change in cash	1	0
Cash and cash equivalents at beginning of period	(8)	0
Cash and cash equivalents at end of period	$ (7)	$ 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

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-Name Accounting Standards Codification

-Glossary Cash

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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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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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