Employee Benefit Plans (Details 2) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Before tax basis amount in accumulated other comprehensive loss.
Total recognized at December 31	$ 9,279	$ 6,749
U.S. [Member]
Before tax basis amount in accumulated other comprehensive loss.
Net actuarial loss	5,982	3,919
Prior service (credit) costs	(44)	(52)
Total recognized at December 31	5,938	3,867
International [Member]
Before tax basis amount in accumulated other comprehensive loss.
Net actuarial loss	2,250	1,903
Prior service (credit) costs	152	179
Total recognized at December 31	2,402	2,082
Other Benefits [Member]
Before tax basis amount in accumulated other comprehensive loss.
Net actuarial loss	1,002	935
Prior service (credit) costs	(63)	(135)
Total recognized at December 31	$ 939	$ 800