Debt and Financing Arrangements Short and Long-term Debt Additional Information (Details)	12 Months Ended							3 Months Ended						12 Months Ended
	Sep. 30, 2014 USD ($)	Sep. 30, 2013 USD ($)	Sep. 30, 2012 USD ($)	Sep. 30, 2014 Revolving Credit Facilities USD ($)	Sep. 30, 2013 Revolving Credit Facilities USD ($)	Sep. 30, 2014 Commercial Paper USD ($)	Sep. 30, 2013 Commercial Paper USD ($)	Sep. 30, 2013 Committed Five-year Credit Facility Revolving Credit Facilities USD ($)	Sep. 30, 2013 Committed Four-year Credit Facility Revolving Credit Facilities USD ($)	Sep. 30, 2014 50 Million Euro Revolving Credit Facility Revolving Credit Facility Expiring August 2015 EUR (€)	Sep. 30, 2014 50 Million Euro Revolving Credit Facility Revolving Credit Facility Expiring September 2015 EUR (€)	Sep. 30, 2014 Euro	Sep. 30, 2013 Euro	Sep. 30, 2014 37 Million Euro Revolving Credit Facility Revolving Credit Facility Expiring September 2015 EUR (€)	Sep. 30, 2014 50 Million USD Revolving Credit Facility Revolving Credit Facility Expiring September 2015 USD ($)
Debt Instrument [Line Items]
Total credit facility available								$ 2,500,000,000.0	$ 2,500,000,000.0	€ 50,000,000	€ 50,000,000			€ 37,000,000	$ 50,000,000
Length of Credit Facility								5 years	4 years
Maximum amount drawn on the credit facilities during period				0	0									0	0
Average outstanding commercial paper						1,252,000,000	1,123,000,000
Outstanding commercial paper at period end						0	0
Weighted-average interest rate of debt												2.00%	3.10%
Interest paid on short and long-term debt	314,000,000	300,000,000	299,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Installments of long-term debt maturing 2015	140,000,000
Installments of long-term debt maturing 2016	915,000,000
Installments of long-term debt maturing 2017	773,000,000
Installments of long-term debt maturing 2018	405,000,000
Installments of long-term debt maturing 2019	295,000,000
Installments of long-term debt maturing 2020 and thereafter	$ 3,969,000,000