Debt (Schedule Of Long-Term Debt) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Capital Lease Obligations	$ 7.5	$ 9.8
Less: Unamortized discount	(7.4)	(9.1)
Long-term debt	3,999.7	3,842.3
Less: Current portion	(72.2)	(182.5)
Total Long-term Debt	3,927.5	3,659.8
Debentures 8.75% [Member]
Senior Notes	18.4	18.4
Debt Instrument, Maturity Date Range, Start	2021
Debt Instrument, Maturity Date Range, End	2021
Interest rate of debt	8.75%
Series D 7.3% [Member]
Medium-term Notes	32.1	63.1
Debt Instrument, Maturity Date Range, Start	2016
Debt Instrument, Maturity Date Range, End	2016
Interest rate of debt	7.30%
Series E 7.6% [Member]
Medium-term Notes	17.2	17.2
Debt Instrument, Maturity Date Range, Start	2026
Debt Instrument, Maturity Date Range, End	2026
Interest rate of debt	7.60%
Series G 4.1% [Member]
Medium-term Notes		125.0
Debt Instrument, Maturity Date Range, Start	2011
Debt Instrument, Maturity Date Range, End	2011
Interest rate of debt	4.10%
Note 4.15% [Member]
Senior Notes	300.0	300.0
Debt Instrument, Maturity Date Range, Start	2013
Debt Instrument, Maturity Date Range, End	2013
Interest rate of debt	4.15%
Note 2.0% [Member]
Senior Notes	350.0
Debt Instrument, Maturity Date Range, Start	2016
Debt Instrument, Maturity Date Range, End	2016
Interest rate of debt	2.00%
Note 4.375% [Member]
Senior Notes	400.0	400.0
Debt Instrument, Maturity Date Range, Start	2019
Debt Instrument, Maturity Date Range, End	2019
Interest rate of debt	4.375%
Variable-Rate Industrial Revenue Bonds 0.1% [Member]
Other Debt	975.1	975.1
Debt Instrument, Maturity Date Range, Start	2016
Debt Instrument, Maturity Date Range, End	2050
Interest rate of debt	0.10%
Other 2.1% [Member]
Other Debt	58.5	55.1
Debt Instrument, Maturity Date Range, Start	2012
Debt Instrument, Maturity Date Range, End	2019
Interest rate of debt	2.10%
Eurobonds 4.25% [Member]
Debt payable in other currencies	401.6	408.1
Debt Instrument, Maturity Date Range, Start	2012
Debt Instrument, Maturity Date Range, End	2012
Interest rate of debt	4.25%
Eurobonds 3.75% [Member]
Debt payable in other currencies	401.6	408.1
Debt Instrument, Maturity Date Range, Start	2014
Debt Instrument, Maturity Date Range, End	2014
Interest rate of debt	3.75%
Eurobonds 3.875% [Member]
Debt payable in other currencies	401.6	408.1
Debt Instrument, Maturity Date Range, Start	2015
Debt Instrument, Maturity Date Range, End	2015
Interest rate of debt	3.875%
Eurobonds 4.625% [Member]
Debt payable in other currencies	401.6	408.1
Debt Instrument, Maturity Date Range, Start	2017
Debt Instrument, Maturity Date Range, End	2017
Interest rate of debt	4.625%
Other 5.1% [Member]
Debt payable in other currencies	241.9	255.3
Debt Instrument, Maturity Date Range, Start	2012
Debt Instrument, Maturity Date Range, End	2018
Interest rate of debt	5.10%
United States 5.0% [Member]
Capital Lease Obligations	4.8	5.5
Debt Instrument, Maturity Date Range, Start	2012
Debt Instrument, Maturity Date Range, End	2018
Interest rate of debt	5.00%
Foreign 3.9% [Member]
Capital Lease Obligations	$ 2.7	$ 4.3
Debt Instrument, Maturity Date Range, Start	2013
Debt Instrument, Maturity Date Range, End	2017
Interest rate of debt	3.90%

Including both current and noncurrent portions, carrying amount as of the balance sheet date of debt denominated in a currency other than the U.S. dollar with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Interest rate stated in the contractual debt agreement.

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When presenting a range of maturity dates, the latest date when the outstanding debt instruments are required to be repaid. May be presented in a variety of ways (for example: year only, month and year, day, month and year, and number of years).

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Total of the portions of the carrying amounts as of the balance sheet date of long-term debt, which may include notes payable, bonds payable, debentures, mortgage loans, and commercial paper, which are scheduled to be repaid within one year or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Including the current and noncurrent portions, carrying value at the balance sheet date of a financial instrument used to receive debt funding on a regular basis with original maturities ranging from 5-10 years.

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Including both current and noncurrent portions, carrying amount as of the balance sheet date of other forms of debt not elsewhere specified in the taxonomy with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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