Pension and Postretirement Benefit Plans (Components of net periodic benefit cost and other information) (Details 2) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
United States Qualified and Non-qualified Pension Benefits
Net periodic benefit cost (benefit)
Service cost	$ 73	$ 60	$ 146	$ 120
Interest cost	164	169	328	338
Expected return on plan assets	(267)	(261)	(534)	(522)
Amortization of transition (asset) obligation	0	0	0	0
Amortization of prior service cost (benefit)	(6)	1	(12)	2
Amortization of net actuarial (gain) loss	102	61	204	122
Net periodic benefit cost (benefit)	66	30	132	60
Settlements, curtailments, special termination benefits and other	0	0	0	0
Net periodic benefit cost (benefit) after settlements, curtailments, special termination benefits and other	66	30	132	60
International Qualified and Non-qualified Pension Benefits
Net periodic benefit cost (benefit)
Service cost	40	35	82	71
Interest cost	55	65	110	129
Expected return on plan assets	(81)	(80)	(162)	(159)
Amortization of transition (asset) obligation	(1)	0	(1)	0
Amortization of prior service cost (benefit)	(3)	(4)	(7)	(8)
Amortization of net actuarial (gain) loss	38	31	76	62
Net periodic benefit cost (benefit)	48	47	98	95
Settlements, curtailments, special termination benefits and other	0	0	(17)	0
Net periodic benefit cost (benefit) after settlements, curtailments, special termination benefits and other	48	47	81	95
Postretirement Benefits
Net periodic benefit cost (benefit)
Service cost	22	17	43	33
Interest cost	25	24	50	48
Expected return on plan assets	(23)	(23)	(45)	(45)
Amortization of transition (asset) obligation	0	0	0	0
Amortization of prior service cost (benefit)	(8)	(12)	(16)	(24)
Amortization of net actuarial (gain) loss	19	15	38	29
Net periodic benefit cost (benefit)	35	21	70	41
Settlements, curtailments, special termination benefits and other	0	0	0	0
Net periodic benefit cost (benefit) after settlements, curtailments, special termination benefits and other	$ 35	$ 21	$ 70	$ 41