Credit Arrangements (Schedule of Long-Term Debt) (Details) - USD ($) $ in Thousands	Aug. 31, 2023	Aug. 31, 2022
Debt Instrument [Line Items]
Total debt	$ 115,710	$ 115,931
Less current portion	(226)	(222)
Less debt issuance costs	(320)	(368)
Total long-term debt	115,164	115,341
Elecsys Series 2006A Bonds [Member]
Debt Instrument [Line Items]
Total debt	710	931
Series A Senior Notes [Member]
Debt Instrument [Line Items]
Total debt	$ 115,000	$ 115,000