Income Taxes - Income Tax Expense (Benefit) by Current and Deferred (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Current:
United States federal	$ 0	$ 0	$ 0
State	2	0	1
Foreign	36	8	0
Current income tax provision (benefit)	38	8	1
Deferred, net of changes in valuation allowances:
United States federal	3	30	0
State	0	1	0
Deferred foreign income tax expense (benefit)	7	2	(92)
Income tax provision (benefit)	$ 48	$ 41	$ (91)