Pension and retirement plans (Periodic Pension Cost) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 30, 2023	Dec. 31, 2022	Dec. 30, 2023	Dec. 31, 2022
Components of net periodic pension costs
Service cost within selling, general and administrative expenses	$ 2,563	$ 3,004	$ 5,126	$ 6,008
Interest cost	6,144	6,683	12,289	13,365
Expected return on plan assets	(9,985)	(12,215)	(19,970)	(24,430)
Amortization of prior service cost	1	1	2	2
Recognized net actuarial loss	55	618	111	1,235
Net periodic pension cost (benefit)	(1,222)	(1,909)	(2,442)	(3,820)
Other Income, net
Components of net periodic pension costs
Net periodic pension cost (benefit)	(3,785)	$ (4,913)	(7,568)	$ (9,828)
Plan
Components of net periodic pension costs
Contributions			4,000
Estimated future employer pension plan contributions	$ 4,000		$ 4,000