Major Classes of Inventory (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Inventories [Line Items]
Raw materials and supplies	$ 7,431	$ 5,934
Semi-finished and finished steel products	80,731	73,046
Operating materials	7,587	6,108
Total inventory, net	$ 95,749	$ 85,088

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Carrying value of operating materials and supplies as of the Balance Sheet date.

+ References

No definition available.

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The aggregated amount of merchandise or goods held by the entity and readily available for future sale plus items held by the entity which are partially complete or in the process of being readied for future sale. This amount is net of valuation reserves and adjustments.

+ References

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

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Carrying amount (lower of cost or market) as of the balance sheet date of inventories less all valuation and other allowances. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer).

+ References

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

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- Definition

Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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