Pension plan (Details ) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Mar. 30, 2013	Mar. 31, 2012	Mar. 30, 2013	Mar. 31, 2012
Components of net periodic pension costs
Service cost	$ 9,230	$ 7,095	$ 27,690	$ 21,285
Interest cost	3,663	3,731	10,989	11,193
Expected return on plan assets	(6,976)	(6,734)	(20,928)	(20,202)
Recognized net actuarial loss	3,724	2,420	11,172	7,260
Amortization of prior service credit	(393)	(469)	(1,179)	(1,407)
Net periodic pension cost	$ 9,248	$ 6,043	$ 27,744	$ 18,129