Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Aug. 31, 2021	Aug. 31, 2020	Aug. 31, 2019
Allowance For Doubtful Accounts [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	$ 2,780	$ 2,635	$ 3,585
Charges to costs and expenses	771	589	0
Charged to other accounts	0	0	0
Deductions	129	444	950
Balance at end of period	3,422	2,780	2,635
Deferred Tax Asset Valuation Allowance [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	3,218	3,759	3,562
Charges to costs and expenses	206	83	197
Charged to other accounts	0	0	0
Deductions	2,333	624	0
Balance at end of period	$ 1,091	$ 3,218	$ 3,759