INVENTORIES (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Inventories
Material on leach pads	$ 9,188	$ 14,267
In-process inventory	5,486	4,953
Stockpiles	1,168	1,102
Precious metals	12,902	5,035
Materials and supplies	3,207	1,263
Current Inventories	31,951	26,620
Inventory write-down	0	0
Other assets
Inventories
Non-current portion of ore on leach pads	$ 10,400	$ 0

Represents the carrying amount, net of reserves and adjustments, as of the balance sheet date, of ore on leach pads.

No definition available.

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- Definition

Represents non-current portion of ore on leach pads which is included in the other assets.

+ References

No definition available.

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- Definition

Carrying amount, net of reserves and adjustments, as of the balance sheet date, of ore stockpiled.

+ References

No definition available.

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- Definition

Represents the carrying amount, net of reserves and adjustments, as of the balance sheet date, of precious metals.

+ References

No definition available.

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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.

+ References

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Aggregated amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed. This amount is net of valuation reserves and adjustments.

+ References

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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.

+ References

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- Definition

Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

+ References

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-Publisher FASB
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