Income Taxes (Reconciliation Of Beginning And Ending Amount Of Unrecognized Tax Benefits) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Tax Expense (Benefit) [Abstract]
Balance at January 1	$ (857)	$ (199)	$ (308)
(Additions) reductions based on tax positions related to current year	12	(2)	(12)
Additions for tax positions of prior years	(140)	(719)	(50)
Reductions for tax positions of prior years	6	29	97
Settlements	2	2	0
Expiration of statutes of limitations	7	25	70
Currency translation adjustment	(2)	7	4
Balance at December 31	$ (972)	$ (857)	$ (199)