Fair Value Measurement (Tables)

12 Months Ended

Sep. 30, 2011

Fair Value Measurements [Abstract]

Financial assets and financial liabilities that are measured at fair value on a recurring basis

	Asset (Liability)
	Quoted Prices
	in Active			Significant
	Markets for			Other
	Identical Assets			Observable			Unobservable
	and Liabilities			Inputs			Inputs
	(Level 1)			(Level 2)			(Level 3)		Total
September 30, 2011:
Assets:
Derivative financial instruments:
Commodity contracts	$	3.5		$	3.3		$	—	$	6.8
Foreign currency contracts	$	—		$	5.3		$	—	$	5.3
Liabilities:
Derivative financial instruments:
Commodity contracts	$	(28.1	)	$	(16.1	)	$	—	$	(44.2	)
Foreign currency contracts	$	—		$	(3.3	)	$	—	$	(3.3	)
Interest rate contracts	$	—		$	(44.4	)	$	—	$	(44.4	)
September 30, 2010:
Assets:
Derivative financial instruments:
Commodity contracts	$	1.1		$	10.7		$	—	$	11.8
Foreign currency contracts	$	—		$	0.8		$	—	$	0.8
Liabilities:
Derivative financial instruments:
Commodity contracts	$	(49.4	)	$	(20.3	)	$	—	$	(69.7	)
Foreign currency contracts	$	—		$	(2.9	)	$	—	$	(2.9	)
Interest rate contracts	$	—		$	(18.5	)	$	—	$	(18.5	)