Disclosures About Derivative Instruments and Hedging Activities (Details 1) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Assets	$ 14.9	$ 12.1
Total Derivatives Liability	(132.9)	(91.9)
Designated as Hedging Instrument [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Assets	8.3	6.3
Total Derivatives Liability	(122.6)	(76.9)
Designated as Hedging Instrument [Member] | Interest Rate Contracts [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	1.3	5.8
Total Derivatives Liability	(0.9)	(3.3)
Derivatives Not Designated as Hedging Instruments [Member] | Commodity Contracts [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Liability	(0.9)	0
Derivatives Not Designated as Hedging Instruments [Member] | Foreign currency contracts [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Assets	0	0
Derivative Financial Instruments and Other Assets [Member] | Designated as Hedging Instrument [Member] | Commodity Contracts [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Assets	6.5	1.1
Derivative Financial Instruments and Other Assets [Member] | Designated as Hedging Instrument [Member] | Foreign currency contracts [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Assets	1.8	5.2
Derivative Financial Instruments and Other Assets [Member] | Derivatives Not Designated as Hedging Instruments [Member] | Commodity Contracts [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Assets	1.3	5.8
Derivative Financial Instruments and Other Noncurrent Liabilities [Member] | Designated as Hedging Instrument [Member] | Commodity Contracts [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Liability	(50.7)	(32.5)
Derivative Financial Instruments and Other Noncurrent Liabilities [Member] | Designated as Hedging Instrument [Member] | Foreign currency contracts [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Liability	0	0
Derivative Financial Instruments and Other Noncurrent Liabilities [Member] | Designated as Hedging Instrument [Member] | Interest Rate Contracts [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Liability	(71.9)	(44.4)
Derivative Financial Instruments and Other Noncurrent Liabilities [Member] | Accounted for Under ASC 980 [Member] | Commodity Contracts [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Liability	(9.4)	(11.7)
Derivative Financial Instruments [Member] | Accounted for Under ASC 980 [Member] | Commodity Contracts [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Assets	5.3	0
Derivative Financial Instruments [Member] | Derivatives Not Designated as Hedging Instruments [Member] | Foreign currency contracts [Member]
Balance sheet location and fair value of derivative assets and liabilities
Total Derivatives Liability	$ 0	$ (3.3)