Inventories (Components of Inventories) (Details) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Inventories
Raw ore	$ 1,313	$ 943
Concentrate and in-process	47,973	40,818
Finished goods	87,705	42,236
Metals inventory	136,991	83,997
Materials and supplies	19,294	17,809
Total inventory	$ 156,285	$ 101,806

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Carrying amount as of the balance sheet date of merchandise or goods held by the company that are readily available 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.

+ References

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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).

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- Definition

The carrying amount of ore stockpile material contained on a leach pad, such as copper or gold ore.

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Carrying amount as of the balance sheet date of merchandise or goods which are partially completed, are generally comprised of raw materials, labor and factory overhead costs, and which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

+ References

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-Publisher SEC
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Carrying amount 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.

+ References

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