Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2012

Assets and Liabilities Measured at Fair Value on Recurring Basis

The following table summarizes assets and liabilities that are measured at fair value on a recurring basis as of September 30, 2012 and December 31, 2011:

	September 30, 2012								December 31, 2011
	Fair Value Asset (Liability)								Fair Value Asset (Liability)
(in millions)	Level 1		Level 2			Total			Level 1		Level 2			Total
Derivatives:
Assets	$	—	$	0.2		$	0.2		$	—	$	4.4		$	4.4
Liabilities		—		(21.0	)		(21.0	)		—		(8.6	)		(8.6	)
Available for sale securities		—		20.5			20.5			—		19.5			19.5