Income Taxes (Schedule of Reconciliation of Unrecognized Tax Benefits Included in Uncertain Tax Positions) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
As of the beginning of the year	$ 207	$ 211	$ 244
Increases in tax positions for the current year	17	6	0
Increases in tax positions for prior years	57	42	37
Decreases in tax positions for prior years	(32)	(19)	(54)
Decreases due to settlements	(2)	(33)	(16)
As of the end of the year	247	207	211
Total unrecognized tax benefits that, if recognized, would impact the effective tax rate	258	237	230
Total amount of interest and penalties recognized in the consolidated statements of operations	4	6	(1)
Total amount of interest and penalties recognized in the consolidated balance sheets	$ 65	$ 61	$ 55