Stock Option Plan - Stock Options Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	May 30, 2020	May 25, 2019
Additional disclosures
Proceeds from option exercises	$ 931	$ 518
Stock Options
Shares
Outstanding at beginning of period (in shares)	2,748,735
Granted (in shares)	194,014
Exercised (in shares)	(76,366)
Forfeited (in shares)	0
Outstanding at end of period (in shares)	2,866,383
Options vested or expected to vest (in shares)	2,866,383
Exercisable (in shares)	1,551,838
Weighted average exercise price
Outstanding at beginning of period (in dollars per share)	$ 13.35
Granted (in dollars per share)	24.20
Exercised (in dollars per share)	12.20
Forfeited (in dollars per share)	0
Outstanding at end of period (in dollars per share)	14.12
Options vested or expected to vest (in dollars per share)	14.12
Exercisable (in dollars per share)	$ 12.70
Weighted average remaining contractual term
Outstanding at end of period, weighted average remaining contractual life	7 years 6 months 7 days
Vested and expected to vest at end of period, weighted average remaining contractual life	7 years 6 months 7 days
Exercisable at end of period, weighted average remaining contractual life	7 years 3 months 7 days
Additional disclosures
Unrecognized compensation costs	$ 3,200
Period for recognition of unrecognized compensation cost	9 months 25 days
Proceeds from option exercises	$ 900