Nature of Operations	12 Months Ended
Aug. 31, 2021
Nature Of Operations [Abstract]
Nature of Operations	Note 1 - Nature of Operations Founded in 1906, Schnitzer Steel Industries, Inc., an Oregon corporation, is one of North America’s largest recyclers of ferrous and nonferrous metal, including end-of-life vehicles, and a manufacturer of finished steel products. Schnitzer Steel Industries, Inc. and its consolidated subsidiaries, together, are referred to as the Company. The Company acquires and recycles ferrous and nonferrous scrap metal for sale to foreign and domestic metal producers, processors, and brokers, and it procures salvaged vehicles and sells serviceable used auto parts from these vehicles through a network of self-service auto parts stores. Most of these auto parts stores supply the Company’s shredding facilities with auto bodies that are processed into saleable recycled metal products. In addition to the sale of recycled metal products processed at its facilities, the Company provides a variety of recycling and related services. The Company also produces a range of finished steel long products at its electric arc furnace (“EAF”) steel mill using recycled ferrous metal sourced internally from its recycling and joint venture operations and other raw materials. As of August 31, 2021, all of the Company’s facilities were located in the United States (“U.S.”) and its territories and Canada.

The entire disclosure for the business description and basis of presentation concepts. Business description describes the nature and type of organization including but not limited to organizational structure as may be applicable to holding companies, parent and subsidiary relationships, business divisions, business units, business segments, affiliates and information about significant ownership of the reporting entity. Basis of presentation describes the underlying basis used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

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