Employee Benefit Plans (Tables)

6 Months Ended

Jun. 27, 2021

Retirement Benefits [Abstract]

Components of Net Periodic Benefit Costs

Components of net periodic benefit cost for the Company's defined benefit plans were as follows (in thousands):

	Three months ended				Six months ended
	June 27, 2021		June 28, 2020		June 27, 2021		June 28, 2020
Pension and SERPA Benefits:
Service cost	$	6,348	$	6,806	$	12,696	$	13,612
Interest cost	15,472		19,111		30,942		38,223
Expected return on plan assets	(32,720)		(33,764)		(65,440)		(67,528)
Amortization of unrecognized:
Prior service credit	(312)		(272)		(624)		(544)
Net loss	18,386		16,372		36,772		32,744
Settlement loss	—		—		816		—
Net periodic benefit cost	$	7,174	$	8,253	$	15,162	$	16,507
Postretirement Healthcare Benefits:
Service cost	$	1,288	$	1,202	$	2,576	$	2,403
Interest cost	1,626		2,336		3,252		4,672
Expected return on plan assets	(3,495)		(3,467)		(6,990)		(6,934)
Amortization of unrecognized:
Prior service credit	(581)		(595)		(1,162)		(1,190)
Net loss	264		123		528		246
Net periodic benefit cost	$	(898)	$	(401)	$	(1,796)	$	(803)