Segment Information - Segment Information (Details) $ in Thousands	3 Months Ended	12 Months Ended
Feb. 28, 2019 USD ($) jointventureinterests segment	Aug. 31, 2018 USD ($) jointventureinterests
Segment Reporting Information [Line Items]
Number of Operating Segments \| segment	2
Number of Equity Method Investments	2	2
Equity Method Investment, Ownership Percentage	50.00%	50.00%
Investments in joint ventures \| $	$ 10,703	$ 11,532
Auto and Metals Recycling
Segment Reporting Information [Line Items]
Number of Joint Venture Investments	1	1
Number of Equity Method Investments, Divested in the Period		2
Investments in joint ventures \| $	$ 3,000	$ 4,000
Cascade Steel and Scrap
Segment Reporting Information [Line Items]
Number of Joint Venture Investments	1	1
Investments in joint ventures \| $	$ 8,000	$ 8,000

Number of entities which were accounted for under the equity method of accounting.

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Number of Equity Method Investments, Divested in the Period

+ References

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- Definition

Number of Joint Venture Investments

+ References

No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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- Definition

Amount of investment in equity method investee and investment in and advance to affiliate.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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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.

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