Derivative Financial Instruments (Details 2) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Fair values of outstanding derivative instruments
Derivative assets	$ 1.7	$ 0.6
Derivative liabilities	5.2	6.7
Interest rate swap agreements | Cash flow hedges
Effect of derivative instruments on income and other comprehensive income
Increase in Losses Recognized in Accumulated Other Comprehensive Loss on Derivatives Before Tax Effect (Effective Portion)	3.7
Derivatives designated as hedging instruments | Foreign currency options | Cash flow hedges
Effect of derivative instruments on income and other comprehensive income
Increase in Losses Recognized in Accumulated Other Comprehensive Loss on Derivatives Before Tax Effect (Effective Portion)	0.1
Derivatives designated as hedging instruments | Foreign currency options | Cash flow hedges | Cost of revenue
Effect of derivative instruments on income and other comprehensive income
Losses Recognized in Income on Derivatives (Amount Excluded from Effectiveness Testing and Ineffective Portion)	(0.1)	(0.1)
Derivatives designated as hedging instruments | Foreign currency options | Prepaid expenses and other current assets
Fair values of outstanding derivative instruments
Derivative assets	0.1	0.1
Derivatives designated as hedging instruments | Interest rate swap agreements | Cash flow hedges
Effect of derivative instruments on income and other comprehensive income
Increase in Losses Recognized in Accumulated Other Comprehensive Loss on Derivatives Before Tax Effect (Effective Portion)	(0.5)	(8.4)
Losses Recognized in Income on Derivatives (Amount Excluded from Effectiveness Testing and Ineffective Portion)	0
Derivatives designated as hedging instruments | Interest rate swap agreements | Cash flow hedges | Other income (expense)
Effect of derivative instruments on income and other comprehensive income
Losses Reclassified from Accumulated Other Comprehensive Loss into Income (Effective Portion)	(3.1)	(2.2)
Derivatives designated as hedging instruments | Interest rate swap agreements | Accrued expenses and other current liabilities
Fair values of outstanding derivative instruments
Derivative liabilities	2.6	2.9
Derivatives designated as hedging instruments | Interest rate swap agreements | Other long-term liabilities
Fair values of outstanding derivative instruments
Derivative liabilities	1.1	3.2
Derivatives not designated as hedging instruments
Effect of derivative instruments on income and other comprehensive income
Non designated derivatives, Gains/(Losses) Recognized in Income on Derivatives (Amount Excluded from Effectiveness Testing and Ineffective Portion)	(5.0)	4.2
Derivatives not designated as hedging instruments | Option contracts | Cost of revenue
Effect of derivative instruments on income and other comprehensive income
Non designated derivatives, Gains/(Losses) Recognized in Income on Derivatives (Amount Excluded from Effectiveness Testing and Ineffective Portion)	(0.3)	(0.1)
Derivatives not designated as hedging instruments | Option contracts | Prepaid expenses and other current assets
Fair values of outstanding derivative instruments
Derivative assets		0.1
Derivatives not designated as hedging instruments | Foreign currency forward contracts | General and administrative expenses
Effect of derivative instruments on income and other comprehensive income
Non designated derivatives, Gains/(Losses) Recognized in Income on Derivatives (Amount Excluded from Effectiveness Testing and Ineffective Portion)	(4.7)	4.2
Derivatives not designated as hedging instruments | Foreign currency forward contracts | Cost of revenue
Effect of derivative instruments on income and other comprehensive income
Non designated derivatives, Gains/(Losses) Recognized in Income on Derivatives (Amount Excluded from Effectiveness Testing and Ineffective Portion)		0.1
Derivatives not designated as hedging instruments | Foreign currency forward contracts | Prepaid expenses and other current assets
Fair values of outstanding derivative instruments
Derivative assets	1.6	0.4
Derivatives not designated as hedging instruments | Foreign currency forward contracts | Accrued expenses and other current liabilities
Fair values of outstanding derivative instruments
Derivative liabilities	$ 1.5	$ 0.6