Employee and Retiree Benefits - Deferred Compensation Narrative (Details) - USD ($)	12 Months Ended
	Aug. 28, 2021	Aug. 29, 2020	Aug. 31, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Matching contribution amount	$ 5,557,000	$ 3,367,000	$ 2,894,000
Employer discretionary contribution amount	$ 6,122,000	0	0
Key Employees | Non-Qualified Deferred Compensation Program (1981)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Vesting age	55 years
Requisite service period	5 years
Requisite service period prior to December 1992	20 years
Deferred compensation expense	$ 795,000	902,000	$ 943,000
Officers and Managers | Supplemental Employee Retirement Plan (SERP)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contractual amount of years after retirement	15 years
Officers and Key Employees | Executive Deferred Compensation Plan 2007
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Maximum salary deferral	50.00%
Maximum cash incentive award deferral	100.00%
Deferred compensation assets	$ 1,027,000	$ 710,000