Derivative Instruments and Fair Value Measurment (Details 2) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Sep. 30, 2011	Jun. 30, 2011	Sep. 30, 2010
Derivative Instruments and Fair Value Measurement (Textual) [Abstract]
Notional values of forward exchange contracts	$ 1,006.2
Notional values of forward exchange contracts designated as cash flow hedges	624.7
Foreign denominated debt designated as net investment hedges	14.0
Net unrealized gains (losses) on cash flow hedges to be reclassified into earnings during the next 12 months	10.4
Net unrealized gains (losses) on cash flow hedges to be reclassified into earnings during the next 12 months, net of tax	6.5
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents, at Carrying Value	805.6	988.9	1,021.8	813.4
Cash and Cash Equivalents, Fair Value Disclosure	805.6
Investments, Fair Value Disclosure	350.0
Short-term Investments	350.0	0
Short-term debt	270.0	0
Short-term Debt, Fair Value	270.0
Long-term debt, Carrying Value	905.0	905.0
Long-term debt, Fair Value	1,223.4	1,125.4
Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	690.3
Investments, Fair Value Disclosure	0
Short-term Debt, Fair Value	0
Long-term debt, Fair Value	0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	115.3
Investments, Fair Value Disclosure	350.0
Short-term Debt, Fair Value	270.0
Long-term debt, Fair Value	1,223.4
Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	0
Investments, Fair Value Disclosure	0
Short-term Debt, Fair Value	0
Long-term debt, Fair Value	$ 0