Commitments and Contingencies (Summary of Environmental Remediation Liability Classifications) (Details) - USD ($) $ in Thousands	Aug. 31, 2021	Aug. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Other current liabilities	$ 965	$ 1,115
Other noncurrent liabilities	15,128	15,030
Total environmental remediation liabilities	$ 16,093	$ 16,145

Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

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