Total costs accrued as of the balance sheet date for environmental loss contingencies.

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The charge against earnings in the period for known or estimated future costs arising from requirements to perform environmental remediation activities.

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Commitments and Contingencies - Recycling Operations - Other Legacy (Details) - USD ($)	12 Months Ended
	Aug. 31, 2020	Aug. 31, 2018	Aug. 31, 2019
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	$ 53,464,000	$ 53,832,000	$ 51,799,000
Legacy Environmental Site 1 - Remediation of Shredder Residue
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	4,000,000		4,000,000
Environmental remediation expense accrued in the period		$ 4,000,000
Legacy Environmental Site 1 - Remediation of Shredder Residue \| Minimum
Loss Contingencies [Line Items]
Loss contingency, range of possible loss	0
Legacy Environmental Site 1 - Remediation of Shredder Residue \| Maximum
Loss Contingencies [Line Items]
Loss contingency, range of possible loss	28,000,000
Legacy Environmental Site 2 - Remediation of Soil and Groundwater Conditions
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	8,000,000		8,000,000
Loss contingency, penalties	2,700,000		$ 2,700,000
Legacy Environmental Site 2 - Installation of Wellhead Treatment \| Minimum
Loss Contingencies [Line Items]
Environmental remediation expense accrued in the period	10,000,000
Legacy Environmental Site 2 - Installation of Wellhead Treatment \| Maximum
Loss Contingencies [Line Items]
Environmental remediation expense accrued in the period	$ 13,000,000