Income Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Income tax [Line Items]
Income tax expense (benefit) from continuing operations	$ 15	$ 83	$ 79	$ 13
Income tax expense (benefit), change in valuation allowance			23
Income tax expense (benefit), special intraperiod allocation			26
Segment, Discontinued Operations [Member]
Income tax [Line Items]
Income tax expense (benefit), special intraperiod allocation			3
Other Comprehensive Income (Loss) [Member]
Income tax [Line Items]
Income tax expense (benefit), special intraperiod allocation			$ 23