Accumulated Other Comprehensive Loss (Roll Forward of Balances in Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Aug. 31, 2022	Aug. 31, 2021
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ (17,933)	$ (20,572)
Current period change	(3,540)	2,639
Balance	(21,473)	(17,933)
Defined Benefit Pension Plan Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(2,843)	(3,228)
Current period change	566	385
Balance	(2,277)	(2,843)
Defined Benefit Pension Plan Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(15,085)	(17,430)
Current period change	(3,839)	2,345
Balance	(18,924)	(15,085)
Unrealized Gain (Loss) on Marketable Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(5)	86
Current period change	(267)	(91)
Balance	$ (272)	$ (5)