Financial Derivatives - Income Statement Location and Fair Value (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Non-designated Hedges
Foreign currency contracts: Other income (expense)	$ 2.6	$ (0.5)	$ 0.5
Designated Hedges
Interest rate swap - ineffectiveness: Other income (expense)	2.2	(3.2)	1.5
Interest rate swap - effectiveness: Interest expense	$ 27.0	$ 25.9	$ 24.5