Postretirement Benefits (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended			1 Months Ended	3 Months Ended		9 Months Ended		1 Months Ended	3 Months Ended		9 Months Ended
	Feb. 29, 2012	Sep. 30, 2013 Pension Benefits	Sep. 30, 2012 Pension Benefits	Sep. 30, 2013 Pension Benefits	Sep. 30, 2012 Pension Benefits	Sep. 30, 2013 U.S. Pension Benefits	Sep. 30, 2012 U.S. Pension Benefits	Sep. 30, 2013 U.S. Pension Benefits	Sep. 30, 2012 U.S. Pension Benefits	Aug. 31, 2012 U.S. Pension Benefits	Feb. 29, 2012 Non-U.S. Pension Benefits	Sep. 30, 2013 Non-U.S. Pension Benefits	Sep. 30, 2012 Non-U.S. Pension Benefits	Sep. 30, 2013 Non-U.S. Pension Benefits	Sep. 30, 2012 Non-U.S. Pension Benefits	Feb. 29, 2012 Other Postretirement Benefits	Sep. 30, 2013 Other Postretirement Benefits	Sep. 30, 2012 Other Postretirement Benefits	Sep. 30, 2013 Other Postretirement Benefits	Sep. 30, 2012 Other Postretirement Benefits
Defined Benefit Plan Disclosure
Defined benefit plan loss of third party receivable																$ 21
Net gain due to facility closure	6
Net increase in liability due to curtailment and remeasurement										243
Net loss recognized in accumulated other comprehensive income/loss due to curtailment and remeasurement										153
Components of net periodic benefit cost
Service cost						49	46	147	138			31	26	93	82		24	23	79	69
Interest cost						147	152	436	460			43	44	128	135		48	55	146	166
Expected return on plan assets						(208)	(204)	(624)	(610)			(59)	(53)	(176)	(160)		(14)	(15)	(42)	(47)
Amortization of:
Transition obligation / (asset)						0	0	0	0			0	0	0	0		1	1	2	2
Prior service cost / (credit)						4	5	13	15			0	1	1	1		(18)	(18)	(55)	(51)
Net actuarial loss / (gain)						136	126	409	374			33	24	99	72		27	25	81	75
Net periodic benefit cost, excluding curtailments, settlements and special termination benefits						128	125	381	377			48	42	145	130		68	71	211	214
Adjustment for subsidiary pension plan						31	0	31	0			0	0	0	0		0	0	0	0
Curtailments, settlements and special termination benefits						0	7	0	7		10	0	6	3	28	(37)	0	0	0	(40)
Total cost included in operating profit						159	132	412	384			48	48	148	158		68	71	211	174
Weighted-average assumptions used to determine net cost:
Discount rate (as a percent)								3.70%	4.30%					3.70%	4.30%				3.70%	4.30%
Expected return on plan assets (as a percent)								7.80%	8.00%					6.70%	7.10%				7.80%	8.00%
Rate of compensation increase (as a percent)								4.50%	4.50%					3.90%	3.90%				4.40%	4.40%
Pension contributions
Contributions to pension plans		118	195	398	488
Expected full year contributions pension plans during the year		$ 500		$ 500