Retirement Plans (Details 6) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
U.S. Pension Plans [Member]
Components of Net Periodic Benefit Cost:
Service cost	$ 66	$ 67	$ 66
Interest cost	145	152	159
Expected return on plan assets	(209)	(179)	(174)
Amortization of net actuarial loss (gain)	55	28	4
Amortization of prior service cost (credit)	1	1	1
Curtailment loss (gain)			4
Net periodic benefit cost	58	69	60
Expense Assumptions:
Discount rate	5.50%	6.25%	7.50%
Expected return on plan assets	8.50%	8.50%	8.50%
Rate of compensation increase	3.20%	4.20%	4.20%
Non-U.S. Pension Plans [Member]
Components of Net Periodic Benefit Cost:
Service cost	34	38	32
Interest cost	70	68	65
Expected return on plan assets	(76)	(64)	(55)
Amortization of net actuarial loss (gain)	12	11	3
Amortization of prior service cost (credit)	2
Special termination benefits			1
Curtailment loss (gain)	(19)	(1)	(2)
Settlement loss	4	2
Divestures gain			(1)
Currency translation adjustment	(2)	2
Net periodic benefit cost	25	56	43
Expense Assumptions:
Discount rate	4.00%	4.75%	5.50%
Expected return on plan assets	5.50%	6.00%	6.00%
Rate of compensation increase	3.00%	3.20%	3.00%
Postretirement Health and Other Benefits [Member]
Components of Net Periodic Benefit Cost:
Service cost	5	4	4
Interest cost	13	14	18
Amortization of net actuarial loss (gain)	2		(3)
Amortization of prior service cost (credit)	(17)	(17)	(7)
Net periodic benefit cost	$ 3	$ 1	$ 12
Expense Assumptions:
Discount rate	5.50%	6.25%	7.50%