Fair Value Measurements (Schedule of the Carrying Values and Fair Values of Financial Instruments) (Details) - USD ($) $ in Millions	Dec. 31, 2015	Sep. 30, 2015
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including current portion carrying value	$ 4,278.4	$ 4,384.7
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including current portion fair value	4,570.1	4,645.7
Interest rate management contract [Member] \| Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	189.6	171.8
Derivative liabilities	0.0	0.8
Interest rate management contract [Member] \| Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	189.6	171.8
Derivative liabilities	0.0	0.8
Forward Exchange Contracts [Member] \| Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	163.0	147.1
Derivative liabilities	90.1	124.4
Forward Exchange Contracts [Member] \| Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	163.0	147.1
Derivative liabilities	$ 90.1	$ 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
-Topic 825
-SubTopic 10
-Section 50
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-Subparagraph (a)
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+ References

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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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