Pension and Other Postretirement Benefits

3 Months Ended

Mar. 31, 2012

Pension and Other Postretirement Benefits

Pension and Other Postretirement Benefits

7.     Pension and Other Postretirement Benefits

        We maintain four funded defined benefit pension plans: two U.S. plans and two Canadian plans. Three of the four plans are closed to new employees. One of our Canadian plans remains open to new employees. We also provide group medical insurance benefits to certain retirees. The specific medical benefits provided to retirees vary by group and location.

        Net periodic benefit cost included the following components:

	Three months ended March 31,
	2012			2011
	(in millions)
Pension Plans
Service cost for benefits earned during the period	$	3.2		$	3.0
Interest cost on projected benefit obligation		8.6			9.1
Expected return on plan assets		(8.6	)		(8.7	)
Amortization of actuarial loss		2.6			1.5
Net periodic benefit cost	$	5.8		$	4.9
Retiree Medical
Service cost for benefits earned during the period	$	0.8		$	0.7
Interest cost on projected benefit obligation		1.0			1.0
Amortization of transition obligation		0.1			0.1
Amortization of actuarial loss		0.3			0.2
Net periodic benefit cost	$	2.2		$	2.0

        Our 2012 consolidated pension funding contributions are estimated to be approximately $20.0 million, of which approximately $1.2 million was funded in the first three months of 2012.

        In addition to our qualified defined benefit pension plans, we also maintain nonqualified supplemental pension plans for highly compensated employees as defined under federal law. The expense recognized for these plans for the three months ended March 31, 2012 and 2011 was insignificant.

        We have defined contribution plans covering substantially all employees. Under these plans, we contribute a fixed percentage of base salary to employees' accounts and match employee contributions up to specified limits. For three months ended March 31, 2012 and 2011 we contributed $3.3 million and $2.8 million, respectively, to the plans.