Inventories (Details) (USD $) In Thousands, unless otherwise specified	Feb. 28, 2015	Aug. 31, 2014
Inventory, Net [Abstract]
Processed and unprocessed scrap metal	$ 143,993us-gaap_InventoryRawMaterials	$ 106,877us-gaap_InventoryRawMaterials
Semi-finished goods (billets)	7,764us-gaap_InventoryWorkInProcess	12,920us-gaap_InventoryWorkInProcess
Finished goods	65,123us-gaap_InventoryFinishedGoods	59,039us-gaap_InventoryFinishedGoods
Supplies	39,051us-gaap_InventorySuppliesNetOfReserves	37,336us-gaap_InventorySuppliesNetOfReserves
Inventories	$ 255,931us-gaap_InventoryNet	$ 216,172us-gaap_InventoryNet

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of products used directly or indirectly in the manufacturing or production process, which may or may not become part of the final product. May also include items used in the storage, presentation or transportation of physical goods.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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