Basis of Presentation and Accounting Policies (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Reconciled Basic and Diluted EPS
Net income	$ 198.1	$ 161.4
Less: Allocation to participating securities	(0.3)	(0.2)
Net income available to common shareowners	$ 197.8	$ 161.2
Basic weighted average outstanding shares	138.6	139.3
Effect of dilutive securities
Stock options	1.6	1.6
Performance shares	0.2	0.3
Diluted weighted average outstanding shares	140.4	141.2
Earnings Per Share, Basic [Abstract]
Basic	$ 1.43	$ 1.16
Earnings Per Share, Diluted [Abstract]
Diluted	$ 1.41	$ 1.14