Fair Value Measurements (Schedule of Fair Value of Assets and Liabilities) (Details) - Fair Value [Member] - USD ($) $ in Millions	Sep. 30, 2016	Sep. 30, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Assets at Fair Value	$ 375.3	$ 318.9
Total Liabilities at Fair Value	95.8	125.2
Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Assets at Fair Value	375.3	318.9
Total Liabilities at Fair Value	95.8	125.2
Interest rate management contract [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] \| Level 2 [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]
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] \| Level 2 [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 probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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+ References

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Fair value of financial and nonfinancial obligations.

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