Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			9 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2014	Jun. 30, 2013	Sep. 30, 2013
Income Tax Disclosures [Line Items]
Deferred Tax Assets, Valuation Allowance	$ 33.7			$ 33.7		$ 31.0
Income tax expense (benefit)	58.7	59.1		196.1	131.9
Effective Income Tax Rate Reconciliation, Percent	34.20%	28.80%		34.80%	29.00%
Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations		9.3
Valuation Allowance, Deferred Tax Asset, Change in Amount			(18.7)
Deferred tax assets net of DTL	$ 616.3			$ 616.3		$ 617.6