Goodwill - Narrative (Details) - USD ($) $ in Thousands	Nov. 30, 2018	Aug. 31, 2018
Goodwill [Line Items]
Goodwill	$ 167,693	$ 168,065
Goodwill, Impaired, Accumulated Impairment Loss	471,000	471,000
Auto and Metals Recycling
Goodwill [Line Items]
Goodwill	167,693	168,065
Reporting Unit \| Auto and Metals Recycling
Goodwill [Line Items]
Goodwill	$ 1,000	$ 1,000

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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- Definition

Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)
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-Publisher FASB
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