Employee Benefits (Details) (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 Periodic Benefit Cost
Net Periodic Pension Benefit Costs	$ 346	$ 286	$ 694	$ 624
U.S. [Member]
Net Periodic Benefit Cost
Service cost	113	93	226	187
Interest cost	109	115	218	231
Expected return on plan assets	(158)	(153)	(317)	(306)
Amortization of prior service credits	(2)	(2)	(4)	(4)
Amortization of actuarial loss	117	78	235	155
Settlement losses/gain	65	53	139	144
Net Periodic Pension Benefit Costs	244	184	497	407
International [Member]
Net Periodic Benefit Cost
Service cost	46	43	90	88
Interest cost	83	80	162	162
Expected return on plan assets	(68)	(66)	(134)	(137)
Amortization of prior service credits	4	6	9	12
Amortization of actuarial loss	37	30	70	56
Curtailment losses		9		36
Net Periodic Pension Benefit Costs	102	102	197	217
Other Benefits [Member]
Net Periodic Benefit Cost
Service cost	15	16	30	30
Interest cost	38	45	77	90
Amortization of prior service credits	(18)	(18)	(36)	(36)
Amortization of actuarial loss	14	15	29	31
Settlement losses/gain			(26)
Net Periodic Pension Benefit Costs	$ 49	$ 58	$ 74	$ 115