Employee Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2019

Retirement Benefits [Abstract]

Components of Net Periodic Benefit Costs

Components of net periodic benefit cost were as follows (in thousands):

	Three months ended
	March 31, 2019			April 1, 2018
Pension and SERPA Benefits
Service cost	$	6,632		$	8,155
Interest cost	21,371			20,590
Expected return on plan assets	(35,581		)	(36,891		)
Amortization of unrecognized:
Prior service credit	(483		)	(106		)
Net loss	11,128			15,819
Curtailment loss	—			1,018
Net periodic benefit cost	$	3,067		$	8,585
Postretirement Healthcare Benefits
Service cost	$	1,184		$	1,812
Interest cost	2,938			2,897
Expected return on plan assets	(3,507		)	(3,541		)
Amortization of unrecognized:
Prior service credit	(595		)	(460		)
Net loss	69			454
Net periodic benefit cost	$	89		$	1,162