Pension plans and other postretirement benefits

3 Months Ended

Mar. 31, 2015

Compensation and Retirement Disclosure [Abstract]

Pension plans and other postretirement benefits

7. Pension plans and other postretirement benefits

The Company provides defined benefit pension and other postretirement benefits (including health care and life insurance benefits) to qualified retired employees. Net periodic benefit cost for defined benefit plans consisted of the following:

	Pension benefits						Other postretirement benefits
	Three months ended March 31
	2015			2014			2015			2014
	(in thousands)
Service cost	$	6,000			5,100			200			150
Interest cost on projected benefit obligation		17,775			17,250			650			675
Expected return on plan assets		(23,575	)		(22,925	)		—			—
Amortization of prior service credit		(1,525	)		(1,650	)		(350	)		(350	)
Amortization of net actuarial loss		11,175			3,350			25			—
Net periodic benefit cost	$	9,850			1,125			525			475

Expense incurred in connection with the Company’s defined contribution pension and retirement savings plans totaled $16,750,000 and $15,732,000 for the three months ended March 31, 2015 and 2014, respectively.