Disclosures About Derivative Instruments and Hedging Activities (Details 1) (USD $) In Millions	Sep. 30, 2011	Sep. 30, 2010
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Assets	$ 12.1	$ 12.6
Total Derivatives Liability	(91.9)	(91.1)
Commodity Contracts [Member] | Derivative Financial Instruments and Other Assets [Member] | Designated as Hedging Instrument [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Assets	1.1	9.2
Commodity Contracts [Member] | Derivative Financial Instruments and Other Assets [Member] | Derivatives Not Designated as Hedging Instruments [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Assets	5.8	2.2
Foreign currency contracts [Member] | Derivative Financial Instruments and Other Assets [Member] | Designated as Hedging Instrument [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Assets	5.2	0.8
Commodity Contracts [Member] | Derivative Financial Instruments and Other Noncurrent Liabilities [Member] | Designated as Hedging Instrument [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Liability	(32.5)	(48.6)
Commodity Contracts [Member] | Derivative Financial Instruments and Other Noncurrent Liabilities [Member] | Accounted for Under ASC 980 [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Liability	(11.7)	(21.1)
Foreign currency contracts [Member] | Derivative Financial Instruments and Other Noncurrent Liabilities [Member] | Designated as Hedging Instrument [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Liability	0	(2.9)
Interest Rate Contracts [Member] | Derivative Financial Instruments and Other Noncurrent Liabilities [Member] | Designated as Hedging Instrument [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Liability	(44.4)	(18.5)
Commodity Contracts [Member] | Derivative Financial Instruments [Member] | Accounted for Under ASC 980 [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Assets	0	0.4
Foreign currency contracts [Member] | Derivative Financial Instruments [Member] | Derivatives Not Designated as Hedging Instruments [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Liability	(3.3)	0
Interest Rate Contracts [Member] | Derivative Financial Instruments [Member] | Designated as Hedging Instrument [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Assets	0	0
Designated as Hedging Instrument [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Assets	6.3	10.0
Total Derivatives Liability	(76.9)	(70.0)
Commodity Contracts [Member] | Derivatives Not Designated as Hedging Instruments [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Liability	0	0
Foreign currency contracts [Member] | Derivatives Not Designated as Hedging Instruments [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Assets	0	0
Derivatives Not Designated as Hedging Instruments [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Assets	5.8	2.2
Total Derivatives Liability	$ (3.3)	$ 0