Components of Net Periodic Benefit Cost (Tables)

6 Months Ended

Jun. 30, 2012

Components of Net Periodic Benefit Cost

Components of net periodic benefit cost

	Three Months Ended June 30,						Six Months Ended June 30,
(in millions)	2012			2011			2012			2011
Service cost — benefits earned during the period	$	3.7		$	3.4		$	7.3		$	6.8
Interest cost on projected benefit obligation	8.5			8.8			17.0			17.7
Expected return on plan assets	(10.9		)	(10.1		)	(21.8		)	(20.2		)
Amortization of unrecognized transition obligation	—			0.1			0.1			0.1
Amortization of prior service cost	0.4			0.5			0.8			1.1
Recognized actuarial net (gain) or loss	7.0			5.9			14.1			11.7
Settlement loss (gain)	—			(2.5		)	3.1			(2.5		)
Net periodic benefit (income) cost	$	8.7		$	6.1		$	20.6		$	14.7