INVENTORY AND LONG-TERM PARTS INVENTORY (Summary of Inventory) (Details) - USD ($) $ in Thousands |
Mar. 31, 2017 |
Dec. 31, 2016 |
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| Inventory [Line Items] | ||
| Finished goods product inventory | $ 52,396 | $ 52,571 |
| In-process mineral inventory | 16,377 | 22,126 |
| Total product inventory | 68,773 | 74,697 |
| Current parts inventory | 17,421 | 19,658 |
| Total current inventory, net | 86,194 | 94,355 |
| Long-term parts inventory, net | 23,731 | 21,037 |
| Total inventory, net | $ 109,925 | $ 115,392 |
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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. No definition available.
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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. No definition available.
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- Definition 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. 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 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 Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or 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, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, 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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