Financial Instruments (Free-standing derivatives) (Details) (Free Standing Derivatives [Member], Nondesignated as Hedges, USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Free standing derivatives
Gain (loss) on derivatives	$ (575)	$ (960)
Interest Rate Contract [Member]
Free standing derivatives
Gain (loss) on derivatives	(24)	(90)
Foreign Exchange Contract [Member]
Free standing derivatives
Gain (loss) on derivatives	(581)	(1,011)
Other Contract [Member]
Free standing derivatives
Gain (loss) on derivatives	$ 30	$ 141