Condensed Consolidated Statements of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Condensed Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 24.0	$ 32.9
Other comprehensive income (loss):
Available-for-sale securities and currency hedges, net of tax of $0.0 million and $0.0 million, respectively	0.2	0.2
Foreign currency translation adjustment, net of tax of $0.0 million and ($0.9) million, respectively	5.5	(3.4)
Items not yet recognized as a component of net periodic pension and postretirement healthcare costs, net of tax of $0.0 million and $0.0 million, respectively		(0.2)
Total other comprehensive income (loss)	5.7	(3.4)
Total comprehensive income	$ 29.7	$ 29.5