Long-Term Debt (Details) - USD ($)	Jul. 27, 2021	Dec. 15, 2016	May 31, 2022	Aug. 31, 2021
Long-term debt
Long-term Debt.			$ 0	$ 0
All-revolving credit facility with a borrowing capacity of $150,000
Long-term debt
Maximum borrowing capacity		$ 150,000
Additional borrowing capacity		$ 50,000
All-revolving credit facility with a borrowing capacity of $150,000 | London Interbank Offered Rate (LIBOR) | Minimum
Long-term debt
Interest rate margin on variable rate basis (as a percent)		1.00%
All-revolving credit facility with a borrowing capacity of $150,000 | London Interbank Offered Rate (LIBOR) | Maximum
Long-term debt
Interest rate margin on variable rate basis (as a percent)		1.75%
New Credit Agreement
Long-term debt
Maximum borrowing capacity	$ 200,000
Additional borrowing capacity	$ 100,000
Net leverage ratio	3.25
Consolidated interest coverage ratio	3.50
Carrying value of direct and indirect domestic subsidiaries			$ 302,914
Applicable interest rate (as a percent)			0.00%
Term of debt	5 years
Amount drawn remained outstanding			$ 0
Term of potential debt	10 years
New Credit Agreement | London Interbank Offered Rate (LIBOR)
Long-term debt
Interest payment due	3 months
New Credit Agreement | London Interbank Offered Rate (LIBOR) | Minimum
Long-term debt
Interest rate margin on variable rate basis (as a percent)	1.00%
New Credit Agreement | London Interbank Offered Rate (LIBOR) | Maximum
Long-term debt
Interest rate margin on variable rate basis (as a percent)	1.75%