Other Income (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended			3 Months Ended	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011 International Segment [Member]	Dec. 31, 2011 International Segment [Member]
Other Income [Abstract]
Gains/(Losses) on extinguishment of debt	$ (14)	$ (66)	$ (139)
Gains/(Losses) on derivatives	(352)	33	64
Currency revaluation gains/(losses)	236	(11)	(92)
Interest and investment income	85	98	109
Insurance Fee Income	65	83	79
Other	266	165	202
Other income, net	286	302	223
Foreign Currency Translation [Abstract]
Foreign currency translation adjustments				$ 72	$ 60