Condensed Consolidating Financial Information of Guarantor Subsidiaries CONDENSED CONSOLIDATING CASH FLOW INFORMATION (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	$ 1,115	$ 495
Net cash used in investing activities	(1,208)	(2,066)
Net cash provided by (used in) financing activities	116	1,602
Effect of foreign exchange rates	(4)	1
Net increase (decrease) in cash and cash equivalents	19	32
Cash and cash equivalents at beginning of period	106	36
Cash and cash equivalents at end of period	125	68
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	21	8
Net cash used in investing activities	(21)	(8)
Net cash provided by (used in) 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 [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	948	515
Net cash used in investing activities	(1,065)	(1,820)
Net cash provided by (used in) financing activities	113	1,315
Effect of foreign exchange rates	0	0
Net increase (decrease) in cash and cash equivalents	(4)	10
Cash and cash equivalents at beginning of period	20	6
Cash and cash equivalents at end of period	16	16
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	3	150
Net cash used in investing activities	0	(154)
Net cash provided by (used in) financing activities	(3)	4
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 [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	150	111
Net cash used in investing activities	(122)	(84)
Net cash provided by (used in) financing activities	(1)	(6)
Effect of foreign exchange rates	(4)	1
Net increase (decrease) in cash and cash equivalents	23	22
Cash and cash equivalents at beginning of period	86	30
Cash and cash equivalents at end of period	109	52
Non Guarantor Subsidiaries SPV [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	(7)	(289)
Net cash used in investing activities	0	0
Net cash provided by (used in) financing activities	7	289
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 [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	0	0
Net cash used in investing activities	0	0
Net cash provided by (used in) 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