Fair Value Measurements (Schedule of the Carrying Values and Fair Values of Financial Instruments) (Details) - USD ($) $ in Millions	Sep. 30, 2016	Sep. 30, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including current portion carrying value	$ 5,289.4	$ 4,384.7
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including current portion carrying value	5,289.4	4,384.7
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including current portion fair value	5,467.2	4,645.7
Interest rate management contract [Member] \| Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	179.9	171.8
Derivative liabilities	12.7	0.8
Interest rate management contract [Member] \| Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	179.9	171.8
Derivative liabilities	12.7	0.8
Forward Exchange Contracts [Member] \| Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	195.4	147.1
Derivative liabilities	83.1	124.4
Forward Exchange Contracts [Member] \| Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	195.4	147.1
Derivative liabilities	$ 83.1	$ 124.4

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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+ References

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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