Employee and Retiree Benefits (Postretirement Health Care and Deferred Compensation Benefits) (Details) - USD ($) $ in Thousands	May. 30, 2015	Aug. 30, 2014
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]
Postretirement health care benefit cost	$ 36,052	$ 36,930
Non-qualified deferred compensation	19,920	21,014
Executive share option plan liability	5,139	5,628
SERP benefit liability	2,806	2,974
Executive deferred compensation	305	213
Officer stock-based compensation	411	627
Total postretirement health care and deferred compensation benefits	64,633	67,386
Less current portion	(5,422)	(4,575)
Postretirement health care and deferred compensation benefits	$ 59,211	$ 62,811