Employee Benefits (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Net Periodic Benefit Cost
Net Periodic Benefit Costs		$ 289	$ 217	$ 567	$ 424
U.S. [Member]
Net Periodic Benefit Cost
Service cost		134	112	269	225
Interest cost		125	123	251	247
Expected return on plan assets		(196)	(197)	(392)	(394)
Amortization of prior service credits		(2)	(2)	(4)	(4)
Amortization of actuarial losses		89	53	178	105
Settlement losses (gains)		54	33	108	66
Net Periodic Benefit Costs		204	122	410	245
International [Member]
Net Periodic Benefit Cost
Service cost		49	50	94	97
Interest cost		72	89	141	173
Expected return on plan assets		(65)	(76)	(130)	(152)
Amortization of prior service credits		6	5	11	10
Amortization of actuarial losses		23	27	41	51
Net Periodic Benefit Costs		85	95	157	179
Other Benefits [Member]
Net Periodic Benefit Cost
Service cost	[1]	18	12	36	25
Interest cost	[1]	37	38	75	75
Amortization of prior service credits	[1]	4	4	7	7
Amortization of actuarial losses	[1]	8	1	17	3
Net Periodic Benefit Costs		$ 67	$ 55	$ 135	$ 110

[1] Includes costs for U.S. and international OPEB plans. Obligations for plans outside the United States are not significant relative to the company’s total OPEB obligation.