Accumulated Other Comprehensive Income (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, December 31, 2012	$ (181)	[1]
Other comprehensive income (loss) before reclassifications	(2)	[1]
Amounts reclassified from accumulated other comprehensive income (2)	1	[1],[2]
Net other comprehensive income (loss)	(1)	[1]
Balance, March 31, 2013	(182)	[1]
Losses on Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, December 31, 2012	(16)	[1]
Other comprehensive income (loss) before reclassifications	0	[1]
Amounts reclassified from accumulated other comprehensive income (2)	1	[1],[2]
Net other comprehensive income (loss)	1	[1]
Balance, March 31, 2013	(15)	[1]
Defined Benefit Pension Items [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, December 31, 2012	(165)	[1]
Other comprehensive income (loss) before reclassifications	0	[1]
Amounts reclassified from accumulated other comprehensive income (2)	0	[1],[2]
Net other comprehensive income (loss)	0	[1]
Balance, March 31, 2013	(165)	[1]
Foreign Currency [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, December 31, 2012	0	[1]
Other comprehensive income (loss) before reclassifications	(2)	[1]
Amounts reclassified from accumulated other comprehensive income (2)	0	[1],[2]
Net other comprehensive income (loss)	(2)	[1]
Balance, March 31, 2013	$ (2)	[1]

[1] All amounts are net of tax.

[2] The amounts reclassified from accumulated other comprehensive income are recorded within interest expense, net on the condensed consolidated statement of income.