Income Taxes (Details 4) (USD $) In Millions	12 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Reconciliation of beginning and ending amount of unrecognized tax benefit
Beginning Balance	$ 5.4	$ 2.3	$ 4.9
Additions for tax positions of the current year	0.4	4.3	0.5
Additions for tax positions of prior years	1.0		0.3
Reductions as a result of tax positions taken in prior years		(0.2)	(1.2)
Settlements with tax authorities	(0.5)	(1.0)	(2.2)
Ending Balance	$ 6.3	$ 5.4	$ 2.3

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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-Glossary Unrecognized Tax Benefit

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The gross amount of decreases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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-Publisher FASB

-Name FASB Interpretation (FIN)

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The gross amount of decreases in unrecognized tax benefits resulting from settlements with taxing authorities.

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The gross amount of increases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns.

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The gross amount of increases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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