Pension and other postretirement benefits

6 Months Ended

Jun. 30, 2012

Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]

Pension and other postretirement benefits

Pension and other postretirement benefits

We have historically provided certain health care benefits for a large number of retired U.S. employees. In addition to our retiree health care plan, we also have a supplemental executive retirement plan in the United States. Further information regarding our postretirement benefit plans can be found under the caption “Note 12: Pension and other postretirement benefits” in the Notes to Consolidated Financial Statements appearing in the 2011 Form 10-K.

Pension and postretirement benefit expense for the quarters ended June 30, 2012 and 2011 consisted of the following components:

	Postretirement benefit plan						Pension plan
	2012			2011			2012		2011
Interest cost	$	1,478		$	1,667		$	37	$	41
Expected return on plan assets	(1,950		)	(1,963		)	—		—
Amortization of prior service credit	(764		)	(936		)	—		—
Amortization of net actuarial losses	1,467			1,354			2		—
Net periodic benefit expense	$	231		$	122		$	39	$	41

Pension and postretirement benefit expense for the six months ended June 30, 2012 and 2011 consisted of the following components:

	Postretirement benefit plan						Pension plan
	2012			2011			2012		2011
Interest cost	$	2,956		$	3,334		$	74	$	82
Expected return on plan assets	(3,901		)	(3,926		)	—		—
Amortization of prior service credit	(1,528		)	(1,871		)	—		—
Amortization of net actuarial losses	2,935			2,708			4		—
Net periodic benefit expense	$	462		$	245		$	78	$	82