Debt (Long-term Debt) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Sep. 30, 2014	Sep. 30, 2013
Debt Instrument [Line Items]
Less: Unamortized discount	$ (5.7)	$ (5.7)
Total Long-term Debt	4,889.8	5,563.7
Less: Current portion of long-term debt	(65.3)	(507.4)
Long-term debt	4,824.5	5,056.3
United States 5.0%
Debt Instrument [Line Items]
Interest rate of debt, stated percentage	5.00%
Debt Instruments Maturity Year	2018
Capital Lease Obligations	1.0	1.3
Foreign 9.2%
Debt Instrument [Line Items]
Interest rate of debt, stated percentage	9.20%
Debt Instrument, Maturity Year Range, Start	2017
Debt Instrument, Maturity Year Range, End	2021
Capital Lease Obligations	1.5	0.3
Debentures 8.75%
Debt Instrument [Line Items]
Interest rate of debt, stated percentage	8.75%
Debt Instruments Maturity Year	2021
Senior Notes	18.4	18.4
Series D 7.3%
Debt Instrument [Line Items]
Weighted average interest rate	7.30%
Debt Instruments Maturity Year	2016
Medium-term Notes	32.1	32.1
Series E 7.6%
Debt Instrument [Line Items]
Weighted average interest rate	7.60%
Debt Instruments Maturity Year	2026
Medium-term Notes	17.2	17.2
Note 2.0%
Debt Instrument [Line Items]
Interest rate of debt, stated percentage	2.00%
Debt Instruments Maturity Year	2016
Senior Notes	350.0	350.0
Note 1.2%
Debt Instrument [Line Items]
Interest rate of debt, stated percentage	1.20%
Debt Instruments Maturity Year	2018
Senior Notes	400.0	400.0
Note 4.375%
Debt Instrument [Line Items]
Interest rate of debt, stated percentage	4.375%
Debt Instruments Maturity Year	2019
Senior Notes	400.0	400.0
Note 3.0%
Debt Instrument [Line Items]
Interest rate of debt, stated percentage	3.00%
Debt Instruments Maturity Year	2022
Senior Notes	400.0	400.0
Note 2.75%
Debt Instrument [Line Items]
Interest rate of debt, stated percentage	2.75%
Debt Instruments Maturity Year	2023
Senior Notes	400.0	400.0
Note 3.35%
Debt Instrument [Line Items]
Interest rate of debt, stated percentage	3.35%
Debt Instruments Maturity Year	2024
Senior Notes	400.0	0
Variable-rate industrial revenue bonds 0.04%
Debt Instrument [Line Items]
Weighted average interest rate	0.04%
Debt Instrument, Maturity Year Range, Start	2021
Debt Instrument, Maturity Year Range, End	2050
Other Long-term Debt	917.1	917.1
Commercial paper 0.1%
Debt Instrument [Line Items]
Weighted average interest rate	0.10%
Debt Instruments Maturity Year	2014
Other Long-term Debt	0	400.0
Other 2.5%
Debt Instrument [Line Items]
Weighted average interest rate	2.50%
Debt Instrument, Maturity Year Range, Start	2015
Debt Instrument, Maturity Year Range, End	2020
Other Long-term Debt	25.3	46.8
Eurobonds 3.75%
Debt Instrument [Line Items]
Interest rate of debt, stated percentage	3.75%
Debt Instruments Maturity Year	2014
Debt Payable In Other Currencies	0	405.7
Eurobonds 3.875%
Debt Instrument [Line Items]
Interest rate of debt, stated percentage	3.875%
Debt Instruments Maturity Year	2015
Debt Payable In Other Currencies	378.9	405.7
RMB Syndicated Credit Facility 4.05%
Debt Instrument [Line Items]
Interest rate of debt, stated percentage	4.05%
Debt Instruments Maturity Year	2014
Debt Payable In Other Currencies	0	40.9
Eurobonds 4.625%
Debt Instrument [Line Items]
Interest rate of debt, stated percentage	4.625%
Debt Instruments Maturity Year	2017
Debt Payable In Other Currencies	378.9	405.7
Eurobonds 2.0%
Debt Instrument [Line Items]
Interest rate of debt, stated percentage	2.00%
Debt Instruments Maturity Year	2020
Debt Payable In Other Currencies	378.9	405.7
CLP Series E bonds 6.3%
Debt Instrument [Line Items]
Interest rate of debt, stated percentage	6.30%
Debt Instruments Maturity Year	2030
Debt Payable In Other Currencies	143.1	163.8
Other 5.6%
Debt Instrument [Line Items]
Interest rate of debt, stated percentage	5.60%
Debt Instrument, Maturity Year Range, Start	2015
Debt Instrument, Maturity Year Range, End	2022
Debt Payable In Other Currencies	$ 253.1	$ 358.7

Latest year the outstanding debt instruments are required to be repaid

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Earliest year the outstanding debt instruments are required to be repaid

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Year the outstanding debt instruments are required to be repaid

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Debt Payable In Other Currencies

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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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Contractual interest rate for funds borrowed, under the debt agreement.

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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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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Weighted average interest rate of long-term debt outstanding.

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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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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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