Financial Instruments (Fair Value of Derivative Instruments) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Sep. 30, 2013
Derivative [Line Items]
Total Derivatives, Assets	$ 117.3	$ 125.9
Total Derivatives, Liabilities	62.4	41.3
Designated as Hedging Instrument [Member]
Derivative [Line Items]
Total Derivatives, Assets	116.3	116.3
Total Derivatives, Liabilities	61.4	39.8
Designated as Hedging Instrument [Member] | Other Receivables [Member] | Interest rate management contract [Member]
Derivative [Line Items]
Total Derivatives, Assets	0	0
Designated as Hedging Instrument [Member] | Other Receivables [Member] | Forward Exchange Contracts [Member]
Derivative [Line Items]
Total Derivatives, Assets	65.1	52.2
Designated as Hedging Instrument [Member] | Other Noncurrent Assets [Member] | Interest rate management contract [Member]
Derivative [Line Items]
Total Derivatives, Assets	49.3	35.4
Designated as Hedging Instrument [Member] | Other Noncurrent Assets [Member] | Forward Exchange Contracts [Member]
Derivative [Line Items]
Total Derivatives, Assets	1.9	28.7
Designated as Hedging Instrument [Member] | Accrued Liabilities [Member] | Interest rate management contract [Member]
Derivative [Line Items]
Total Derivatives, Liabilities	3.4	3.5
Designated as Hedging Instrument [Member] | Accrued Liabilities [Member] | Forward Exchange Contracts [Member]
Derivative [Line Items]
Total Derivatives, Liabilities	25.0	22.5
Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member] | Interest rate management contract [Member]
Derivative [Line Items]
Total Derivatives, Liabilities	4.4	6.1
Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member] | Forward Exchange Contracts [Member]
Derivative [Line Items]
Total Derivatives, Liabilities	28.6	7.7
Hedges Not Designated [Member] | Other Receivables [Member] | Forward Exchange Contracts [Member]
Derivative [Line Items]
Total Derivatives, Assets	1.0	9.6
Hedges Not Designated [Member] | Accrued Liabilities [Member] | Forward Exchange Contracts [Member]
Derivative [Line Items]
Total Derivatives, Liabilities	$ 1.0	$ 1.5