Income Taxes (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Jun. 30, 2011	Sep. 30, 2010
Unrecognized tax benefits
Gross Unrecognized Tax Benefits	$ 75.2	$ 66.3
Net Unrecognized Tax Benefits	35.9	15.2
Offsetting Tax Benefits	39.3	51.1
Income Taxes (Textuals) [Abstract]
Effective income tax rate	19.00%
Statutory tax rate	35.00%
Discrete tax benefits, net	21.0
Reasonably possible amount of increase/ (decrease) in unrecognized tax benefits for the next twelve months	4.9
Reasonably possible amount of increase/ (decrease) in offsetting tax benefits for the next twelve months	10.5
Accrued interest for tax	16.5	24.9
Penalties for tax	1.2	1.7
Continuing operations [Member]
Unrecognized tax benefits
Gross Unrecognized Tax Benefits	66.7
Net Unrecognized Tax Benefits	30.4
Offsetting Tax Benefits	$ 36.3

Unusual or infrequent tax benefits, net of unusual or infrequent tax expenses, which do not relate to "ordinary income" in the current year. Discrete tax items are accounted for in the period in which they occur.

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Income Taxes Textuals.

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The reasonably possible amount of Offsetting Tax Benefits that could increase or decrease within twelve months of the balance sheet date as result of the resolution of worldwide tax matters, the lapses of statutes of limitations, and changes in estimate due to a significant event (e.g. a court ruling).

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

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Unrecognized Tax Benefits.

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The amount of Gross Unrecognized Tax Benefits less the amount of Offsetting Tax Benefits.

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A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

+ References

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-Publisher FASB
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-Publisher SEC
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The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
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-Paragraph 21
-Subparagraph d
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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.

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-Publisher FASB
-Name FASB Interpretation (FIN)
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This element represents the amount of statutory penalties accrued as of the date of the statement of financial position for a tax position claimed or expected to be claimed by the entity, in its tax return, that does not meet the minimum statutory threshold to avoid payment of penalties.

+ References

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This element represents the amount of interest expense accrued as of the date of the statement of financial position for an underpayment of income taxes computed by applying the applicable statutory rate of interest to the difference between a tax position recognized for financial reporting purposes and the amount previously taken or expected to be taken in a tax return of the entity.

+ References

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