Commitments and Contingencies (Summary of Undiscounted Environmental Remediation Liability Classifications) (Details) - USD ($) $ in Thousands	Nov. 30, 2020	Aug. 31, 2020	Nov. 30, 2019
Commitments And Contingencies Disclosure [Abstract]
Other current liabilities	$ 1,105	$ 1,115	$ 1,243
Other noncurrent liabilities	15,021	15,030	14,548
Total environmental remediation liabilities	$ 16,126	$ 16,145	$ 15,791

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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