Segment Information Segment Assets Reconciliation to Consolidated (Details) - USD ($) $ in Thousands	May 31, 2018	Aug. 31, 2017
Segment Reporting Information [Line Items]
Assets	$ 1,077,270	$ 933,755
Investments in joint ventures	11,635	11,204
Auto and Metals Recycling
Segment Reporting Information [Line Items]
Investments in joint ventures	4,000	5,000
Cascade Steel and Scrap
Segment Reporting Information [Line Items]
Investments in joint ventures	7,000	7,000
Operating Segments
Segment Reporting Information [Line Items]
Assets	2,174,919	1,995,026
Operating Segments \| Auto and Metals Recycling
Segment Reporting Information [Line Items]
Assets	1,449,838	1,298,757
Operating Segments \| Cascade Steel and Scrap
Segment Reporting Information [Line Items]
Assets	725,081	696,269
Corporate and eliminations
Segment Reporting Information [Line Items]
Assets	$ (1,097,649)	$ (1,061,271)

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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