Commitments and Contingencies (Summary of Undiscounted Environmental Remediation Liability Classifications) (Details) - USD ($) $ in Thousands	Aug. 31, 2019	Aug. 31, 2018
Commitments And Contingencies Disclosure [Abstract]
Other current liabilities	$ 1,243	$ 1,264
Other noncurrent liabilities	14,674	15,319
Total environmental remediation liabilities	$ 15,917	$ 16,583

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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