Pension Plan and Postretirement Benefits Other Than Pension (Tables)

9 Months Ended

Sep. 30, 2012

Pension Plan and Postretirement Benefits Other Than Pension

Schedule of components of net periodic pension and other postretirement costs and assumptions related to those costs

	Pension Benefits					Other Postretirement Benefits		Pension Benefits				Other Postretirement Benefits
	Three months ended  September 30,					Three months ended September 30,		Nine months ended September 30,				Nine months ended September 30,
	2012			2011		2012	2011	2012		2011		2012	2011
	(in thousands)							(in thousands)
Components of net periodic benefit cost:
Service cost	$	2,343		1,775		173	139	7,030		5,326		519	418
Interest cost	1,893			1,799		100	100	5,678		5,397		300	301
Expected return on plan assets	(2,200		)	(2,191	)	—	—	(6,600	)	(6,573	)	—	—
Actuarial loss amortization	1,141			451		3	—	3,422		1,353		9	—
Prior service cost amortization	139			139		14	14	417		417		42	42
Transition obligation amortization	1			1		—	—	4		3		—	—
Total	$	3,317		1,974		290	253	9,951		5,923		870	761