Leases (Supplemental Balance Sheet Information) (Details) - USD ($) $ in Thousands	9 Months Ended
	May 29, 2021	Aug. 29, 2020	May 30, 2020
Leases [Abstract]
Operating lease assets	$ 39,401	$ 56,173
Finance lease assets	2,674	3,625
Total leased assets	42,075	59,798
Current operating lease liabilities	14,570	21,815
Current finance lease liabilities	1,291	1,262
Noncurrent operating lease liabilities	26,008	34,379
Noncurrent finance lease liabilities	1,473	2,453
Total lease liabilities	$ 43,342	59,909
Weighted average remaining lease term (years), Operating leases	4 years 6 months		3 years 10 months 24 days
Weighted average remaining lease term (years), Finance leases	2 years 2 months 12 days		3 years 2 months 12 days
Weighted average discount rate, Operating leases	3.50%		3.40%
Weighted average discount rate, Finance leases	2.70%		2.70%
Finance lease right of use assets, Accumulated amortization	$ 2,405	$ 1,439
Operating lease impairment loss net of gains related to settlement of lease liabilities	$ 14,458