Employee Benefit Plans - Amounts Recorded in Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Aug. 29, 2020	Aug. 31, 2019
Pension Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Deferred tax assets	$ 279	$ 254
Accrued liabilities	1,322	963
Accumulated other comprehensive loss	(819)	(741)
SERP
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Deferred tax assets	3,144	2,912
Accrued liabilities	38,616	35,967
Accumulated other comprehensive loss	$ (9,234)	$ (8,509)