The amount of advanced project cost.

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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. Includes expenses classified as other.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets. Includes the cash outflow from the purchase of mining and mining related assets during the period.

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Represents the amount of residual leaching and other site costs.

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Segment income or loss for the period.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of expense for allocation of cost of tangible and intangible assets over their useful lives, and reduction in quantity of natural resource due to consumption directly used in production of good and rendering of service.

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Cost of product sold and service rendered, excluding depreciation, depletion, and amortization.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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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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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount of other expense that is infrequent in occurrence or unusual in nature.

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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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OPERATING SEGMENT REPORTING (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Operating Segment Reporting
Inventory	$ 33,371			$ 33,371		$ 38,376
Revenue from gold and silver sales	18,291		$ 36,383	49,691	$ 51,966
Production costs applicable to sales	(22,354)		(24,699)	(50,741)	(35,848)
Depreciation and depletion	(4,812)		(7,007)	(11,510)	(10,013)
Gross (loss) profit	(8,875)		4,677	(12,560)	6,105
Advanced projects	(2,887)		(2,095)	(5,437)	(4,741)
Impairment of mineral property interests and plant and equipment (note 8)		$ (83,800)		(83,805)
Loss from investment in Minera Santa Cruz S.A. (note 8)	(1,045)		(4,137)	(3,721)	(6,447)
Segment (loss) income	(18,323)		(7,427)	(114,829)	(15,105)
General and Administrative and other	(1,521)		(6,088)	(5,300)	(8,428)
Loss before income and mining taxes	(19,844)		(13,515)	(120,129)	(23,533)
Capital expenditures	3,010		8,124	8,546	24,489
Other operating	(1,968)			(1,968)
El Gallo Project
Operating Segment Reporting
Inventory	2,000		1,800	2,000	1,800
Production costs applicable to sales				(7,300)	(10,700)
Sunk costs				3,100	3,800
U.S.
Operating Segment Reporting
Depreciation and depletion	(2,565)		(2,568)	(6,428)	(2,720)
Gross (loss) profit	(2,834)		1,119	(9,411)	1,001
Advanced projects	(183)		(390)	(548)	(586)
Impairment of mineral property interests and plant and equipment (note 8)				(83,805)
Segment (loss) income	(6,438)		(563)	(97,994)	(1,487)
Capital expenditures	2,799		3,606	4,606	16,614
Other operating	(1,390)			(1,390)
Canada
Operating Segment Reporting
Depreciation and depletion	(2,184)		(4,221)	(4,932)	(6,931)
Gross (loss) profit	(6,168)		1,189	(3,384)	1,586
Advanced projects	(1,760)			(2,826)
Segment (loss) income	(9,346)		(2,873)	(10,033)	(4,897)
Capital expenditures	211		4,518	3,940	7,875
Other operating	(578)			(578)
Mexico
Operating Segment Reporting
Depreciation and depletion	(63)		(218)	(150)	(362)
Gross (loss) profit	127		2,369	235	3,518
Advanced projects	(944)		(1,705)	(2,063)	(4,155)
Segment (loss) income	(853)		664	(1,864)	(637)
MSC
Operating Segment Reporting
Loss from investment in Minera Santa Cruz S.A. (note 8)	(1,045)		(4,137)	(3,721)	(6,447)
Segment (loss) income	(1,045)		(4,137)	(3,721)	(6,447)
Los Azules
Operating Segment Reporting
Segment (loss) income	(641)		(518)	(1,217)	(1,637)
MSC
Operating Segment Reporting
Revenue from gold and silver sales	47,081		65,997	84,471	114,818
Production costs applicable to sales	(30,402)		(46,514)	(58,718)	(76,047)
Depreciation and depletion	(7,650)		(16,545)	(14,977)	(31,925)
Gross (loss) profit	9,029		2,938	10,776	6,846
Loss from investment in Minera Santa Cruz S.A. (note 8)	(1,045)		(4,137)	(3,721)	(6,447)
Loss before income and mining taxes	(2,071)		(594)	(5,407)	(2,577)
Gold and silver sales
Operating Segment Reporting
Revenue from gold and silver sales	18,291		36,383	49,691	51,966
Gold and silver sales \| U.S.
Operating Segment Reporting
Revenue from gold and silver sales	10,770		11,522	25,088	12,364
Gold and silver sales \| Canada
Operating Segment Reporting
Revenue from gold and silver sales	4,166		16,049	16,905	24,992
Gold and silver sales \| Mexico
Operating Segment Reporting
Revenue from gold and silver sales	3,355		8,812	7,698	14,610
Production costs applicable to sales
Operating Segment Reporting
Production costs applicable to sales	(22,354)		(24,699)	(50,741)	(35,848)
Production costs applicable to sales \| U.S.
Operating Segment Reporting
Production costs applicable to sales	(11,039)		(7,835)	(28,071)	(8,643)
Production costs applicable to sales \| Canada
Operating Segment Reporting
Production costs applicable to sales	(8,150)		(10,639)	(15,357)	(16,475)
Production costs applicable to sales \| Mexico
Operating Segment Reporting
Production costs applicable to sales	(3,165)		(6,225)	(7,313)	(10,730)
Exploration
Operating Segment Reporting
Production costs applicable to sales	(3,548)		(5,872)	(7,338)	(10,022)
Exploration \| U.S.
Operating Segment Reporting
Production costs applicable to sales	(2,031)		(1,292)	(2,840)	(1,902)
Exploration \| Canada
Operating Segment Reporting
Production costs applicable to sales	(840)		(4,062)	(3,245)	(6,483)
Exploration \| Mexico
Operating Segment Reporting
Production costs applicable to sales	(36)			(36)
Exploration \| Los Azules
Operating Segment Reporting
Production costs applicable to sales	$ (641)		$ (518)	$ (1,217)	$ (1,637)