Pension and retirement plans (Tables)

9 Months Ended

Mar. 28, 2020

Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]

Components of net periodic pension costs

	Third Quarters Ended				Nine Months Ended
	March 28,		March 30,		March 28,		March 30,
	2020		2019		2020		2019
	(Thousands)
Service cost	$	3,786	$	3,582	$	11,358	$	11,050
Total net periodic pension cost within selling, general and administrative expenses		3,786		3,582		11,358		11,050
Interest cost		5,638		8,010		16,914		21,238
Expected return on plan assets		(12,668)		(16,003)		(38,003)		(42,605)
Amortization of prior service cost (credit)		534		(392)		1,603		(1,178)
Recognized net actuarial loss		3,658		2,091		10,972		7,161
Total net periodic pension benefit within other (expense) income, net		(2,838)		(6,294)		(8,514)		(15,384)
Net periodic pension cost (benefit)	$	948	$	(2,712)	$	2,844	$	(4,334)