Pension and retirement plans (Periodic Pension Cost) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 01, 2022	Jan. 02, 2021	Jan. 01, 2022	Jan. 02, 2021
Components of net periodic pension costs
Service cost	$ 3,751	$ 3,937	$ 7,503	$ 7,875
Interest cost	3,947	3,976	7,894	7,952
Expected return on plan assets	(12,284)	(12,420)	(24,568)	(24,840)
Amortization of prior service cost	1	76	2	151
Recognized net actuarial loss	4,086	5,151	8,172	10,302
Net periodic pension (benefit) cost	(499)	720	(997)	1,440
Selling, General and Administrative Expenses
Components of net periodic pension costs
Net periodic pension (benefit) cost	3,751	3,937	7,503	7,875
Other Income, net
Components of net periodic pension costs
Net periodic pension (benefit) cost	(4,250)	$ (3,217)	(8,500)	$ (6,435)
Plan
Components of net periodic pension costs
Contributions			8,000
Estimated future employer pension plan contributions	$ 8,000		$ 8,000