Financial Instruments (Fair Value of Derivative Instruments) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Sep. 30, 2012
Derivative [Line Items]
Total Derivatives, Assets	$ 121.9	$ 127.6
Total Derivatives, Liabilities	34.6	46.8
Designated as Hedging Instrument [Member]
Derivative [Line Items]
Total Derivatives, Assets	120.4	126.7
Total Derivatives, Liabilities	33.6	44.6
Designated as Hedging Instrument [Member] | Other Receivables [Member] | Interest rate management contract [Member]
Derivative [Line Items]
Total Derivatives, Assets	0.3	1.1
Designated as Hedging Instrument [Member] | Other Receivables [Member] | Forward Exchange Contracts [Member]
Derivative [Line Items]
Total Derivatives, Assets	38.2	12.7
Designated as Hedging Instrument [Member] | Other Noncurrent Assets [Member] | Interest rate management contract [Member]
Derivative [Line Items]
Total Derivatives, Assets	45.5	48.6
Designated as Hedging Instrument [Member] | Other Noncurrent Assets [Member] | Forward Exchange Contracts [Member]
Derivative [Line Items]
Total Derivatives, Assets	36.4	64.3
Designated as Hedging Instrument [Member] | Accrued Liabilities [Member] | Interest rate management contract [Member]
Derivative [Line Items]
Total Derivatives, Liabilities	12.7	15.6
Designated as Hedging Instrument [Member] | Accrued Liabilities [Member] | Forward Exchange Contracts [Member]
Derivative [Line Items]
Total Derivatives, Liabilities	11.7	17.0
Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member] | Interest rate management contract [Member]
Derivative [Line Items]
Total Derivatives, Liabilities	7.1	9.5
Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member] | Forward Exchange Contracts [Member]
Derivative [Line Items]
Total Derivatives, Liabilities	2.1	2.5
Hedges Not Designated [Member] | Other Receivables [Member]
Derivative [Line Items]
Total Derivatives, Assets	1.5	0.9
Hedges Not Designated [Member] | Accrued Liabilities [Member]
Derivative [Line Items]
Total Derivatives, Liabilities	$ 1.0	$ 2.2