Pension and retirement plans (Periodic Pension Cost) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 03, 2021	Mar. 28, 2020	Apr. 03, 2021	Mar. 28, 2020
Components of net periodic pension costs
Service cost	$ 3,938	$ 3,786	$ 11,813	$ 11,358
Interest cost	3,976	5,638	11,928	16,914
Expected return on plan assets	(12,421)	(12,668)	(37,261)	(38,003)
Amortization of prior service cost	75	534	226	1,603
Recognized net actuarial loss	5,151	3,658	15,453	10,972
Net periodic pension cost	719	948	2,159	2,844
Selling, General and Administrative Expenses
Components of net periodic pension costs
Net periodic pension cost	3,938	3,786	11,813	11,358
Other Income, net
Components of net periodic pension costs
Net periodic pension cost	(3,219)	$ (2,838)	(9,654)	$ (8,514)
Plan
Components of net periodic pension costs
Contributions			12,000
Estimated future employer pension plan contributions	$ 4,000		$ 4,000