Fair Value Measurements (Schedule of the Carrying Values and Fair Values of Financial Instruments) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other liabilities		$ 51.0
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including current portion	4,658.5	3,999.7
Other liabilities		51.0
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including current portion	5,005.9	4,284.5
Other liabilities	0	51.0
Interest rate management contract [Member] | Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	49.7	48.2
Derivative liabilities	25.1	6.0
Interest rate management contract [Member] | Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	49.7	48.2
Derivative liabilities	25.1	6.0
Forward Exchange Contracts [Member] | Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	77.9	70.0
Derivative liabilities	21.7	37.8
Forward Exchange Contracts [Member] | Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	77.9	70.0
Derivative liabilities	$ 21.7	$ 37.8