Pension and Other Postretirement Benefits (Tables)

3 Months Ended

Mar. 31, 2017

Compensation and Retirement Disclosure [Abstract]

Schedule of Net Benefit Costs

Pension and other postretirement benefits expenses consisted of the following:

	Three months ended March 31,
Pensions	2017			2016
Service cost	$	1,643		$	1,384
Interest cost	4,621			4,836
Expected return on plan assets	(6,860		)	(7,543		)
Amortization of prior service cost	109			50
Amortization of actuarial losses	2,480			2,556
Settlement gain	(261		)	—
Net periodic benefit cost	$	1,732		$	1,283

	Three months ended March 31,
Other Postretirement Benefits	2017			2016
Service cost	$	22		$	34
Interest cost	389			453
Amortization of prior service credit	(17		)	(93		)
Amortization of actuarial losses	69			176
Net periodic benefit cost	$	463		$	570