Employee Retirement Plans (Tables)

9 Months Ended

Sep. 30, 2011

Employee Retirement Plans [Abstract]

Components of net retirement cost

	Three Months Ended						Nine Months Ended
	September 30,						September 30,
	2011			2010			2011			2010
				(in millions)
Service cost	$	0.2		$	0.2		$	0.7		$	0.7
Interest		4.9			4.4			14.7			14.2
Expected return on plan assets		(5.7	)		(5.0	)		(17.1	)		(15.0	)
Actuarial loss		0.4			0.4			1.4			1.6
Prior service cost		0.1			—			0.1			—
Profit sharing		1.9			2.0			6.4			6.3
Net expense	$	1.8		$	2.0		$	6.2		$	7.8