Document and Entity Information	9 Months Ended
May 31, 2011	Jun. 24, 2011 Class A Common Stock [Member]	Jun. 24, 2011 Class B Common Stock [Member]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	May 31, 2011
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	Q3
Entity Registrant Name	SCHNITZER STEEL INDUSTRIES INC
Entity Central Index Key	0000912603
Current Fiscal Year End Date	--08-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		24,463,409	3,091,401

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The type of document being provided (such as 10-K, 10-Q, N-1A, etc). The document type should be limited to the same value as the supporting SEC submission type. The acceptable values are as follows: S-1, S-3, S-4, S-11, F-1, F-3, F-4, F-9, F-10, 6-K, 8-K, 10, 10-K, 10-Q, 20-F, 40-F, N-1A, 485BPOS, NCSR, N-Q, and Other.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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