Income Taxes (Source of Income (Loss) Before Income Taxes) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Sources of Income (Loss) Before Income Taxes
Income from continuing operations before income taxes	$ 1,221	$ 1,861	$ 1,668
Discontinued operations before income taxes	0	(2,235)	(1,931)
Income (loss) before income tax	$ 1,221	$ (374)	$ (263)