Commitments and Contingencies - Steel Manufacturing Operations (Details) T in Thousands	3 Months Ended
Nov. 30, 2018 USD ($) T	Aug. 31, 2018 USD ($)
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	$ 53,601,000	$ 53,832,000
Steel Manufacturing Operations
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	$ 0	$ 0
Permitted Annual Production Capacity \| T	950
Permit, Renewal Period	5 years

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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