Inventories (Components Of Inventories) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Metals inventory
Raw ore	$ 4,390	$ 4,984
Concentrate and in-process	56,091us-gaap_InventoryWorkInProcess	48,712us-gaap_InventoryWorkInProcess
Finished goods	36,265us-gaap_InventoryFinishedGoods	49,885us-gaap_InventoryFinishedGoods
Total metals inventory	96,746us-gaap_InventoryGross	103,581us-gaap_InventoryGross
Materials and supplies	26,626us-gaap_OtherInventorySupplies	26,726us-gaap_OtherInventorySupplies
Total inventory	$ 123,372us-gaap_InventoryNet	$ 130,307us-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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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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Amount before last-in first-out (LIFO) and valuation reserves of ore stockpile material contained on a leach pad, for example, but not limited to, copper or gold ore.

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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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Amount before valuation and LIFO reserves of other supplies used within the manufacturing or production process expected to be consumed within one year or operating cycle, if longer.

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