Inventory (Major Classes of Inventory) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Raw materials and starting stock	$ 9,815	$ 9,555
Semi-finished and finished steel products	127,713	115,627
Operating materials	13,090	12,515
Gross inventory	150,618	137,697
Inventory reserves	(3,216)	(2,959)
Total inventory, net	$ 147,402	$ 134,738

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Amount before valuation reserves of merchandise or goods held by the entity that are readily available for sale and items held by the entity which are partially complete or in the process of being readied for sale.

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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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

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Amount of valuation reserve for inventory.

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

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