Summary of Significant Accounting Policies	9 Months Ended
May 31, 2011
General Policies [Abstract]
Significant Accounting Policies [Text Block]	Summary of Significant Accounting Policies Basis of Presentation The accompanying unaudited condensed consolidated financial statements of Schnitzer Steel Industries, Inc. (the “Company”) have been prepared pursuant to generally accepted accounting principles in the United States of America (“US GAAP”) for interim financial information and the rules and regulations of the United States Securities and Exchange Commission (the “SEC”) for Form 10-Q, including Article 10 of Regulation S-X. The year-end condensed consolidated balance sheet was derived from audited financial statements, but does not include all disclosures required by US GAAP. Certain information and note disclosures normally included in annual financial statements have been condensed or omitted pursuant to those rules and regulations. In the opinion of management, all normal, recurring adjustments considered necessary for a fair presentation have been included. Although management believes the disclosures made are adequate to ensure the information presented is not misleading, management suggests that these unaudited condensed consolidated financial statements be read in conjunction with the financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended August 31, 2010. The results for the three and nine months ended May 31, 2011 and 2010 are not necessarily indicative of the results of operations for the entire year. Cash and Cash Equivalents Cash and cash equivalents include short-term securities that are not restricted by third parties and have an original maturity date of 90 days or less. Included in accounts payable are book overdrafts of $41 million as of May 31, 2011 and $25 million as of August 31, 2010. Derivative Financial Instruments From time to time the Company enters into forward exchange contracts as a hedge against foreign currency asset and liability commitments and anticipated transaction exposures. The Company records derivative instruments in the consolidated balance sheets at fair value and changes in the fair value are either recognized in accumulated other comprehensive income or net income in the consolidated balance sheets or the consolidated statements of income, as applicable, depending on the nature of the underlying exposure, whether the derivative has been designated as a hedge, and if designated as a hedge, the extent to which the hedge is effective. Derivative contracts for commodities used in normal business operations that are settled by physical delivery, among other criteria, are eligible for and may be designated as normal purchases and normal sales pursuant to the exemption from the accounting requirements of ASC 815 “Derivatives and Hedging” (“ASC 815”). Contracts that qualify as normal purchases or normal sales are not marked-to-market. The Company does not use financial instruments for trading or speculative purposes. When available, quoted market prices or prices obtained through external sources are used to measure a contract’s fair value. The fair value of these instruments is a function of underlying forward commodity prices, related volatility, counterparty creditworthiness and duration of the contracts. Refer to Note 10 - Derivative Financial Instruments. Redeemable Noncontrolling Interest The Company has issued redeemable common stock to the noncontrolling interest holder of one of our subsidiaries that is redeemable both at the option of the holder and upon the occurrence of an event that is not solely within the Company’s control. If the interest were to be redeemed, the Company would be required to purchase all of such interest at fair value on the date of redemption. The Company estimates fair value using Level 3 inputs under the fair value hierarchy based on standard valuation techniques using a discounted cash flow analysis. Any adjustments to the carrying amount of the redeemable noncontrolling interest prior to exercise of the redemption option will be recorded to equity. Since redemption of the noncontrolling interest is outside of the Company’s control, these interests are presented on the condensed consolidated balance sheet in the mezzanine section under the caption “Redeemable noncontrolling interests.” The determination of fair value requires management to apply significant judgment in formulating estimates and assumptions. These estimates and assumptions primarily include forecasts of future cash flows based on management’s best estimate of future sales and operating costs; pricing expectations; capital expenditures; working capital requirements; discount rates; growth rates; tax rates; and general market conditions. Foreign Currency Translation and Transactions Assets and liabilities of foreign operations are translated into US dollars at the period-end exchange rate and revenues and expenses of foreign operations are translated into US dollars at the average exchange rate for the period. Translation adjustments are not included in determining net income for the period, but are recorded in accumulated other comprehensive income (loss), a separate component of SSI shareholders’ equity. Foreign currency transaction gains and losses are generated from the effects of exchange rate changes on transactions denominated in a currency other than the functional currency of the Company, which is the US dollar. The functional currency for the Company’s Canadian operations is the Canadian dollar. Gains and losses on foreign currency transactions are generally required to be recognized in the determination of net income for the period. The Company records these gains and losses in other income (expense), net. Net realized and unrealized foreign currency transaction gains (losses) were less than ($1) million and $2 million for the three and nine months ended May 31, 2011, respectively. The Company did not have any realized or unrealized foreign currency transaction gains or losses for the three and nine months ended May 31, 2010. Recent Accounting Pronouncements In December 2010, an accounting standard update was issued regarding the interpretation of the disclosure of supplementary pro forma information for business combinations. The standard clarifies that an entity is required to disclose pro forma revenue and earnings as though the business combination(s) that occurred during the current year had occurred as of the beginning of the comparable prior annual reporting period only. In addition, this standard expands the supplemental pro forma disclosures to include a description of the nature and amount of material, nonrecurring pro forma adjustments directly attributable to the business combination included in the reported pro forma revenue and earnings. This standard will be effective for the Company for fiscal year 2012. The Company currently complies with these disclosures and thus this standard will not have any impact on previously issued financial statements. In May 2011, an accounting standard update was issued to clarify existing fair value measurement guidance and expand the disclosure requirements for fair value measurements estimated using unobservable inputs (Level 3 inputs). New disclosures are required to report quantitative information about the unobservable inputs used in the measurement of Level 3 valuations and to include the valuation process used to determine the fair value of the item and the sensitivity of the measurement to changes in unobservable inputs. This standard will be effective for the Company for the third quarter of fiscal year 2012. The standard is unlikely to impact the fair value measurement of any of the Company’s existing assets, liabilities, or equity valuations, but additional disclosures will be required for the Company’s redeemable noncontrolling interest, which is measured using Level 3 inputs. In June 2011, an accounting standard update was issued regarding the presentation of other comprehensive income in the financial statements. The standard eliminates the option of presenting other comprehensive income as part of the statement of changes in stockholders’ equity and instead requires the entity to present other comprehensive income as either a single statement of comprehensive income combined with net income or as two separate but continuous statements. This amendment will be effective for the Company for fiscal year 2012. The Company currently reports other comprehensive income in the summary of changes in equity and comprehensive income and will be required to update the presentation of comprehensive income to be in compliance with the new standard.

Summary of Significant Accounting Policies

Basis of Presentation

The accompanying unaudited condensed consolidated financial statements of Schnitzer Steel Industries, Inc. (the “Company”) have been prepared pursuant to generally accepted accounting principles in the United States of America (“US GAAP”) for interim financial information and the rules and regulations of the United States Securities and Exchange Commission (the “SEC”) for Form 10-Q, including Article 10 of Regulation S-X. The year-end condensed consolidated balance sheet was derived from audited financial statements, but does not include all disclosures required by US GAAP. Certain information and note disclosures normally included in annual financial statements have been condensed or omitted pursuant to those rules and regulations. In the opinion of management, all normal, recurring adjustments considered necessary for a fair presentation have been included. Although management believes the disclosures made are adequate to ensure the information presented is not misleading, management suggests that these unaudited condensed consolidated financial statements be read in conjunction with the financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended August 31, 2010. The results for the three and nine months ended May 31, 2011 and 2010 are not necessarily indicative of the results of operations for the entire year.

Cash and Cash Equivalents

Cash and cash equivalents include short-term securities that are not restricted by third parties and have an original maturity date of 90 days or less. Included in accounts payable are book overdrafts of $41 million as of May 31, 2011 and $25 million as of August 31, 2010.

Derivative Financial Instruments

From time to time the Company enters into forward exchange contracts as a hedge against foreign currency asset and liability commitments and anticipated transaction exposures. The Company records derivative instruments in the consolidated balance sheets at fair value and changes in the fair value are either recognized in accumulated other comprehensive income or net income in the consolidated balance sheets or the consolidated statements of income, as applicable, depending on the nature of the underlying exposure, whether the derivative has been designated as a hedge, and if designated as a hedge, the extent to which the hedge is effective. Derivative contracts for commodities used in normal business operations that are settled by physical delivery, among other criteria, are eligible for and may be designated as normal purchases and normal sales pursuant to the exemption from the accounting requirements of ASC 815 “Derivatives and Hedging” (“ASC 815”). Contracts that qualify as normal purchases or normal sales are not marked-to-market. The Company does not use financial instruments for trading or speculative purposes.

When available, quoted market prices or prices obtained through external sources are used to measure a contract’s fair value. The fair value of these instruments is a function of underlying forward commodity prices, related volatility, counterparty creditworthiness and duration of the contracts. Refer to Note 10 - Derivative Financial Instruments.

Redeemable Noncontrolling Interest

The Company has issued redeemable common stock to the noncontrolling interest holder of one of our subsidiaries that is redeemable both at the option of the holder and upon the occurrence of an event that is not solely within the Company’s control. If the interest were to be redeemed, the Company would be required to purchase all of such interest at fair value on the date of redemption. The Company estimates fair value using Level 3 inputs under the fair value hierarchy based on standard valuation techniques using a discounted cash flow analysis. Any adjustments to the carrying amount of the redeemable noncontrolling interest prior to exercise of the redemption option will be recorded to equity. Since redemption of the noncontrolling interest is outside of the Company’s control, these interests are presented on the condensed consolidated balance sheet in the mezzanine section under the caption “Redeemable noncontrolling interests.”

The determination of fair value requires management to apply significant judgment in formulating estimates and assumptions. These estimates and assumptions primarily include forecasts of future cash flows based on management’s best estimate of future sales and operating costs; pricing expectations; capital expenditures; working capital requirements; discount rates; growth rates; tax rates; and general market conditions.

Foreign Currency Translation and Transactions

Assets and liabilities of foreign operations are translated into US dollars at the period-end exchange rate and revenues and expenses of foreign operations are translated into US dollars at the average exchange rate for the period. Translation adjustments are not included in determining net income for the period, but are recorded in accumulated other comprehensive income (loss), a separate component of SSI shareholders’ equity. Foreign currency transaction gains and losses are generated from the effects of exchange rate changes on transactions denominated in a currency other than the functional currency of the Company, which is the US dollar. The functional currency for the Company’s Canadian operations is the Canadian dollar. Gains and losses on foreign currency transactions are generally required to be recognized in the determination of net income for the period. The Company records these gains and losses in other income (expense), net.

Net realized and unrealized foreign currency transaction gains (losses) were less than ($1) million and $2 million for the three and nine months ended May 31, 2011, respectively. The Company did not have any realized or unrealized foreign currency transaction gains or losses for the three and nine months ended May 31, 2010.

Recent Accounting Pronouncements

In December 2010, an accounting standard update was issued regarding the interpretation of the disclosure of supplementary pro forma information for business combinations. The standard clarifies that an entity is required to disclose pro forma revenue and earnings as though the business combination(s) that occurred during the current year had occurred as of the beginning of the comparable prior annual reporting period only. In addition, this standard expands the supplemental pro forma disclosures to include a description of the nature and amount of material, nonrecurring pro forma adjustments directly attributable to the business combination included in the reported pro forma revenue and earnings. This standard will be effective for the Company for fiscal year 2012. The Company currently complies with these disclosures and thus this standard will not have any impact on previously issued financial statements.

In May 2011, an accounting standard update was issued to clarify existing fair value measurement guidance and expand the disclosure requirements for fair value measurements estimated using unobservable inputs (Level 3 inputs). New disclosures are required to report quantitative information about the unobservable inputs used in the measurement of Level 3 valuations and to include the valuation process used to determine the fair value of the item and the sensitivity of the measurement to changes in unobservable inputs. This standard will be effective for the Company for the third quarter of fiscal year 2012. The standard is unlikely to impact the fair value measurement of any of the Company’s existing assets, liabilities, or equity valuations, but additional disclosures will be required for the Company’s redeemable noncontrolling interest, which is measured using Level 3 inputs.

In June 2011, an accounting standard update was issued regarding the presentation of other comprehensive income in the financial statements. The standard eliminates the option of presenting other comprehensive income as part of the statement of changes in stockholders’ equity and instead requires the entity to present other comprehensive income as either a single statement of comprehensive income combined with net income or as two separate but continuous statements. This amendment will be effective for the Company for fiscal year 2012. The Company currently reports other comprehensive income in the summary of changes in equity and comprehensive income and will be required to update the presentation of comprehensive income to be in compliance with the new standard.