Retirement Plans (Schedule of Amounts Recognized in Statement of Financial Position) (Details) - USD ($) $ in Thousands	Aug. 31, 2020	Aug. 31, 2019	Aug. 31, 2018
Compensation And Retirement Disclosure [Abstract]
Other current liabilities	$ 530	$ 530
Pension benefit liabilities	6,374	6,029
Net amount recognized	$ 6,904	$ 6,559	$ 6,404

Amount of liability, recognized in statement of financial position, for defined benefit pension plan. Excludes other postretirement benefit plan.

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-Publisher FASB
-Name Accounting Standards Codification
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Name:	us-gaap_DefinedBenefitPensionPlanCurrentAndNoncurrentLiabilities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant