Employee Benefit Plans (Net Periodic Benefit Costs) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Pension Benefits U.S. Plans
Components of net periodic benefit costs
Service costs	$ 54	$ 50	$ 108	$ 100
Interest costs	101	109	202	218
Expected return on plan assets	(135)	(118)	(269)	(237)
Amortization of net actuarial (gains) losses	47	44	94	85
Amortization of prior service costs (credit)	0	0	0	1
Net periodic benefit costs	67	85	135	167
Pension Benefits Non-U.S. Plans
Components of net periodic benefit costs
Service costs	15	14	30	34
Interest costs	6	4	10	7
Expected return on plan assets	(1)	(2)	(3)	(4)
Amortization of net actuarial (gains) losses	0	0	1	0
Amortization of prior service costs (credit)	0	0	0	0
Net periodic benefit costs	20	16	38	37
Other Postretirement Benefits U.S. Plans
Components of net periodic benefit costs
Service costs	4	4	8	7
Interest costs	22	23	44	46
Expected return on plan assets	(20)	(18)	(40)	(37)
Amortization of net actuarial (gains) losses	11	3	21	6
Amortization of prior service costs (credit)	(1)	(1)	(2)	(1)
Net periodic benefit costs	16	11	31	21
Other Postretirement Benefits Non-U.S. Plans
Components of net periodic benefit costs
Service costs	1	1	1	1
Interest costs	0	0	1	1
Expected return on plan assets	0	(1)	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	$ 1	$ 0	$ 2	$ 1