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Income Taxes (Reconciliation of Statutory Taxes to Effective Taxes) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Income Tax Disclosure [Abstract]
Tax at U.S. federal statutory income tax rate of 35%	$ 25.7	$ 15.5	$ 0.9
Adjustments to reconcile to income tax expense (benefit):
Federal Valuation Allowance	(1.2)	(7.8)	0
Effective Income Tax Rate Reconciliation, Change in State Deferred TAx Assets Valuation Allowance, Amount.	(8.4)	(1.1)	5.9
State income taxes, net of federal benefit	3.6	2.0	(0.8)
State tax rate change	(2.5)	0	0
State valuation allowance, net of federal benefit	(0.6)	(0.3)	0.2
Tax Credits	(0.1)	(0.6)	(0.1)
Other nondeductible expenses	0.9	0.5	0.7
Foreign income taxes	(0.2)	0.4	(0.3)
Nondeductible compensation	0.8	0.2	1.4
Income Tax Expense (Benefit)	$ 18.0	$ 8.8	$ 7.9

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the apportion-weighted state statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for state income tax deferred tax assets.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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