Employee Benefit Plans (Net Periodic Benefit Costs) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Pension Benefits U.S. Plans
Components of net periodic benefit costs
Service costs	$ 54	$ 50	$ 162	$ 150
Interest costs	101	109	303	327
Settlement and curtailment costs	0	14	0	14
Expected return on plan assets	(134)	(119)	(403)	(356)
Amortization of net actuarial (gains) losses	47	42	141	127
Amortization of prior service costs (credit)	(1)	0	(1)	1
Net periodic benefit costs	67	96	202	263
Pension Benefits Non-U.S. Plans
Components of net periodic benefit costs
Service costs	14	17	44	51
Interest costs	5	3	15	10
Settlement and curtailment costs	0	0	0	0
Expected return on plan assets	(2)	(2)	(5)	(6)
Amortization of net actuarial (gains) losses	1	0	2	0
Amortization of prior service costs (credit)	0	0	0	0
Net periodic benefit costs	18	18	56	55
Other Postretirement Benefits U.S. Plans
Components of net periodic benefit costs
Service costs	3	3	11	10
Interest costs	22	23	66	69
Settlement and curtailment costs	0	0	0	0
Expected return on plan assets	(19)	(19)	(59)	(56)
Amortization of net actuarial (gains) losses	10	3	31	9
Amortization of prior service costs (credit)	0	0	(2)	(1)
Net periodic benefit costs	16	10	47	31
Other Postretirement Benefits Non-U.S. Plans
Components of net periodic benefit costs
Service costs	0	0	1	1
Interest costs	0	1	1	2
Settlement and curtailment costs	0	0	0	0
Expected return on plan assets	0	0	0	(1)
Amortization of net actuarial (gains) losses	0	0	0	0
Amortization of prior service costs (credit)	0	0	0	0
Net periodic benefit costs	$ 0	$ 1	$ 2	$ 2