Employee Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2020

Retirement Benefits [Abstract]

Schedule of net periodic benefit cost

The components of net periodic benefit cost for the Company’s defined benefit and other post-retirement plans included the following: 

	Three months ended June 30,				Six months ended June 30,
Components of Net Period Benefit Cost	2020		2019		2020		2019
	(in thousands)
Service cost	$	2,667	$	2,096	$	5,334	$	4,192
Other cost:
Interest cost	4,970		5,608		9,939		11,216
Expected return on plan assets	(6,286)		(5,483)		(12,573)		(10,966)
Recognized net actuarial loss	978		887		1,957		1,774
Total other components of the net periodic benefit cost	(338)		1,012		(677)		2,024
Net periodic benefit cost	$	2,329	$	3,108	$	4,657	$	6,216