Postemployment Benefit Plans (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Net periodic benefit costs, before tax
Service cost	$ 21	$ 14	$ 61	$ 47
Interest cost	20	21	63	62
Expected return on plan assets	(20)	(20)	(64)	(64)
Settlements and curtailments	19	1	21	2
Actuarial losses, net	12	7	34	19
Prior service cost, net	(1)		(2)	(2)
Transition obligation, net		(1)
Net periodic benefit costs	51	22	113	64
Funding contributions	12	9	134	93
U.S. Plans
Net periodic benefit costs, before tax
Service cost	13	10	37	32
Interest cost	15	15	44	44
Expected return on plan assets	(16)	(15)	(47)	(47)
Settlements and curtailments		1	2	2
Actuarial losses, net	11	5	31	17
Prior service cost, net			(1)	(1)
Net periodic benefit costs	23	16	66	47
Funding contributions	1	1	104	69
Non-U.S. Plans
Net periodic benefit costs, before tax
Service cost	7	4	23	14
Interest cost	4	5	17	16
Expected return on plan assets	(4)	(5)	(17)	(17)
Settlements and curtailments	19		19
Actuarial losses, net	1	2	3	2
Prior service cost, net	(1)	1	(1)	1
Transition obligation, net		(1)
Net periodic benefit costs	26	6	44	16
Funding contributions	10	7	27	20
OPEB Plans
Net periodic benefit costs, before tax
Service cost	1		1	1
Interest cost	1	1	2	2
Prior service cost, net		(1)		(2)
Net periodic benefit costs	2		3	1
Funding contributions	$ 1	$ 1	$ 3	$ 4