OPERATING SEGMENT REPORTING (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Operating Segment Reporting
Gold and silver sales	$ 13,430	$ 13,423	$ 43,373	$ 49,226
Production costs applicable to sales	(8,649)	(6,409)	(24,193)	(21,239)
Mine development costs	(1,382)	(934)	(3,217)	(2,948)
Exploration costs	(2,356)	(2,166)	(13,886)	(5,595)
Property holding costs	(1,979)	(1,892)	(3,590)	(3,297)
General and administrative expenses	(4,734)	(3,233)	(13,105)	(8,601)
Income (loss) on investment in Minera Santa Cruz S.A. (net of amortization)	(462)	4,693	(535)	13,789
Depreciation	316	312	1,125	809
Reclamation and Remediation			337		$ 506
Revision of estimates and accretion of reclamation obligations	(320)	(125)	(541)	(382)
Gain on sale of assets		24	11	24
Gain on sale of marketable securities			(840)	(22)
Other-than-temporary impairment on marketable equity securities	(356)		(356)	(882)
Unrealized gain on derivative instrument	(933)	(197)	136	1,522
Foreign currency (loss) gain	(276)	130	799	632
Net Income before income taxes	(8,636)	3,601	(15,867)	22,216
Revenues	13,430	13,423	43,373	49,226
Long-Lived Assets	462,587		462,587		419,744
Investment in MSC	154,590		154,590		162,320
Mexico
Operating Segment Reporting
Gold and silver sales	13,430	13,423	43,373	49,226
Production costs applicable to sales	(8,649)	(6,409)	(24,193)	(21,239)
Mine development costs	(273)	(341)	(605)	(1,038)
Exploration costs	(1,149)	(1,094)	(4,201)	(2,739)
Property holding costs	(1,044)	(812)	(2,089)	(1,642)
General and administrative expenses	(715)	(474)	(2,594)	(1,963)
Segment income (loss)	1,600	4,293	9,691	20,605
MSC
Operating Segment Reporting
Income (loss) on investment in Minera Santa Cruz S.A. (net of amortization)	(462)	4,693	(535)	13,789
Segment income (loss)	(462)	4,693	(535)	13,789
Los Azules
Operating Segment Reporting
Exploration costs	(365)	(543)	(7,507)	(1,046)
Property holding costs		(192)	(48)	(367)
General and administrative expenses	(320)	(234)	(949)	(419)
Segment income (loss)	(685)	(969)	(8,504)	(1,832)
Nevada
Operating Segment Reporting
Mine development costs	(1,109)	(593)	(2,612)	(1,910)
Exploration costs	(556)	(506)	(1,487)	(1,692)
Property holding costs	(935)	(888)	(1,453)	(1,288)
General and administrative expenses	(441)	(69)	(1,226)	(176)
Segment income (loss)	(3,041)	(2,056)	(6,778)	(5,066)
Timmins
Operating Segment Reporting
Exploration costs	(137)		(267)
General and administrative expenses	(32)		(58)
Segment income (loss)	(169)		(325)
Total Segment
Operating Segment Reporting
Gold and silver sales	13,430	13,423	43,373	49,226
Production costs applicable to sales	(8,649)	(6,409)	(24,193)	(21,239)
Mine development costs	(1,382)	(934)	(3,217)	(2,948)
Exploration costs	(2,207)	(2,143)	(13,462)	(5,477)
Property holding costs	(1,979)		(3,590)
General and administrative expenses	(1,508)	(777)	(4,827)	(2,558)
Income (loss) on investment in Minera Santa Cruz S.A. (net of amortization)	(462)	4,693	(535)	13,789
Segment income (loss)	(2,757)	5,961	(6,451)	27,496
Corporate & Other
Operating Segment Reporting
Exploration costs	(149)	(23)	(424)	(118)
General and administrative expenses	(3,226)	(2,456)	(8,278)	(6,043)
Depreciation	(316)	(312)	(1,125)	(809)
Revision of estimates and accretion of reclamation obligations	(320)	(125)	(541)	(382)
Interest income and other income	(303)	599	(478)	754
Gain on sale of assets			11
Gain on sale of marketable securities			840	22
Other-than-temporary impairment on marketable equity securities				882
Unrealized gain on derivative instrument	(933)	(197)	136	1,522
Foreign currency (loss) gain	(276)	130	799	632
Net Income before income taxes	(8,636)	3,601	(15,867)	22,216
MSC
Operating Segment Reporting
Income (loss) on investment in Minera Santa Cruz S.A. (net of amortization)	(462)	4,693	(535)	13,789
Investment in MSC	154,590		154,590		162,320	$ 167,107
Canada
Operating Segment Reporting
Long-Lived Assets	42,555		42,555		663
Mexico
Operating Segment Reporting
Revenues	13,430	$ 13,423	43,373	$ 49,226
Long-Lived Assets	36,879		36,879		27,582
United States
Operating Segment Reporting
Long-Lived Assets	37,071		37,071		37,620
Argentina
Operating Segment Reporting
Long-Lived Assets	$ 346,082		$ 346,082		$ 353,879

Gross amount of expense recognized during the period that is associated with an asset retirement obligation.

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The net amount of operating interest and other income (expense).

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Segment income or loss for the period.

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Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

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The costs incurred to retain exploration and property rights after acquisition but before production has occurred. Costs include legal costs for title defense, ad valorem taxes on nonproducing mineral properties, shut-in royalties, and delay rentals.

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Total costs related to goods produced and sold during the reporting period.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Exploration expenses (including prospecting) related to the mining industry would be included in operating expenses. Exploration costs include costs incurred in identifying areas that may warrant examination and in examining specific areas that are considered to have prospects of mineral reserves.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

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This item represents the total realized gain (loss) included in earnings for the period as a result of selling marketable securities categorized as trading, available-for-sale, or held-to-maturity.

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Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

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The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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Aggregate revenue from the sale of minerals and related products, and from rendering services such as exploration, development, mining, processing and providing mining support activities.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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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.

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