Income Taxes (Details 4) (USD $) In Millions, unless otherwise specified	12 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Unrecognized tax benefits, excluding interest and penalties
Gross unrecognized tax benefits balance at beginning of year	$ 75.1	$ 66.3	$ 116.7
Additions based on tax positions related to the current year		22.3	6.3
Additions based on tax positions related to prior years	3.3	9.3	1.0
Reductions based on tax positions related to prior years		(0.6)	(12.0)
Reductions related to settlements with taxing authorities	(6.3)	(18.5)	(44.0)
Reductions related to lapses of statute of limitations	(2.4)	(3.0)	(3.7)
Effect of foreign currency translation	0.6	(0.7)	2.0
Gross unrecognized tax benefits balance at end of year	70.3	75.1	66.3
Offsetting tax benefits	(47.0)	(44.9)	(51.1)
Net unrecognized tax benefits	$ 23.3	$ 30.2	$ 15.2

Increases / (reductions) in unrecognized tax benefits resulting from fluctuations in foreign currency exchange rates.

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The amount of tax benefits related to deferred tax assets and tax receivables related to Gross Unrecognized Tax Benefits.

+ References

No definition available.

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The amount of gross unrecognized tax benefits less the amount of offsetting tax benefits.

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No definition available.

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

+ References

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-Publisher FASB

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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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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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The gross amount of decreases in unrecognized tax benefits resulting from lapses of the applicable statutes of limitations.

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