Stock-based Compensation - Summary of Stock Based Compensation Recognized under Stock Incentive Plan (Details) - Stock Incentive Plan - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	May 31, 2022	May 31, 2021	May 31, 2022	May 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	$ 732	$ 391	$ 1,771	$ 966
Restaurant-level Stock-based Compensation Included In Other Costs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	88	34	195	83
Corporate-level Stock-based Compensation Included In General and Administrative Expenses
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	$ 644	$ 357	$ 1,576	$ 883