Financial Instruments (Net investment hedges in foreign operations) (Details) (Net Investment Hedge [Member], USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Net investment hedges in foreign operation
Hedge ineffectiveness gain (loss)	$ (260)	$ (377)	$ (480)	$ (655)
Foreign Exchange Contract [Member]
Net investment hedges in foreign operation
Gain (loss) recognized in AOCI	1,853	(2,605)	351	(3,406)
Gain (loss) reclassified from AOCI into earnings	$ (2)	$ (360)	$ (12)	$ (698)