Employee Benefits (Tables)

3 Months Ended

Mar. 31, 2013

Compensation and Retirement Disclosure [Abstract]

Pension and Other Postretirement Benefit Costs

	Pension
	Three Months Ended
	March 31,
	2013			2012
	(in millions)
Service cost	$	1.0		$	1.0
Interest cost	1.2			1.2
Expected return on plan assets	(1.0		)	(0.9		)
Amortization of prior service costs	1.2			1.3
Amortization of actuarial loss	0.6			0.2
Periodic expense	$	3.0		$	2.8

	Postretirement Benefits
	Three Months Ended
	March 31,
	2013		2012
	(in millions)
Service cost	$	—	$	—
Interest cost	0.1		0.1
Amortization of prior service costs	0.1		0.1
Recognized net actuarial loss	—		—
Periodic expense	$	0.2	$	0.2