Employee Benefit Plans - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Aug. 28, 2021	Aug. 29, 2020	Aug. 31, 2019
Pension Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 71	$ 113	$ 114
Interest cost	104	131	260
Expected return on assets	(131)	(138)	(199)
Amortization of prior service cost	55	66	66
Amortization of net loss	36	12	51
Other events	49		503
Net periodic benefit cost	184	184	795
SERP
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	1,100	918	725
Interest cost	943	1,027	1,148
Expected return on assets			0
Amortization of prior service cost			0
Amortization of net loss	821	703	247
Other events			0
Net periodic benefit cost	$ 2,864	$ 2,648	$ 2,120