INVENTORY AND LONG-TERM PARTS INVENTORY (Details) (USD $) | 3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Sep. 30, 2011 | Sep. 30, 2010 | Sep. 30, 2011 | Sep. 30, 2010 | Dec. 31, 2010 | |
| INVENTORY AND LONG-TERM PARTS INVENTORY | |||||
| Product inventory | $ 30,324,000 | $ 30,324,000 | $ 24,398,000 | ||
| In-process mineral inventory | 8,983,000 | 8,983,000 | 11,160,000 | ||
| Current parts inventory | 14,113,000 | 14,113,000 | 12,536,000 | ||
| Total current inventory | 53,420,000 | 53,420,000 | 48,094,000 | ||
| Long-term parts inventory | 8,791,000 | 8,791,000 | 7,121,000 | ||
| Total inventory | 62,211,000 | 62,211,000 | 55,215,000 | ||
| Product inventory impairment charge | 200,000 | 100,000 | 700,000 | 700,000 | |
| Product inventory abnormal production charge | $ 0 | $ 500,000 | |||
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- Definition The charge against earnings in the period to reduce the carrying amount of product inventory to fair value.
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- Definition Including current and noncurrent portions, aggregate carrying amount of inventories, less all valuation and other allowances, as of the balance sheet date.
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- Definition Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of parts inventory, including critical spares, that is not expected to be utilized within a period of one year.
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- Details
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- Definition Carrying amount as of the balance sheet date of merchandise or goods held by the company that are readily available for sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 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). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date for elements of machinery or equipment held for the purpose of replacing similar parts in the course of repair or maintenance. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Nonrecurring impairment charges related to the write-off of production-related equipment and inventory. This tag is used when an Entity charges this cost to cost of goods sold. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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