The amount of advanced project cost.

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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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The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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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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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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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								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Segment Reporting
Inventory	$ 38,376				$ 22,039				$ 38,376	$ 22,039
Revenue from gold and silver sales									117,019	128,175	$ 67,465
Depreciation and depletion									(24,753)	(15,079)	(4,036)
Gross profit	1,261	$ 1,619	$ 4,677	$ 1,429	2,749	$ 6,013	$ 9,092	$ 14,228	8,986	32,082	20,080
Advanced projects									(9,520)	(15,063)	(11,129)
Loss from investment in Minera Santa Cruz S.A.									(8,754)	(11,865)	(44)
Impairment of mineral property interests and property and equipment											(711)
Loss before income and mining taxes									(63,591)	(47,640)	(26,003)
Capital expenditures									30,270	97,468	11,511
El Gallo Project
Operating Segment Reporting
Operating expenditures									11,600
Inventory	3,400								3,400
Cost of goods and services sold									(8,200)
Sunk costs									10,300
U.S.
Operating Segment Reporting
Depreciation and depletion									(10,934)
Gross profit									(701)
Advanced projects									(649)	(7,959)	(6,686)
Segment (loss) income									(9,904)	(13,133)	(8,818)
Capital expenditures									18,806	84,713	6,271
Canada
Operating Segment Reporting
Depreciation and depletion									(13,271)	(12,972)	(1,737)
Gross profit									5,666	5,957	1,732
Advanced projects									(1,636)
Segment (loss) income									(21,749)	(16,075)	71
Capital expenditures									11,464	12,584	4,301
Mexico
Operating Segment Reporting
Depreciation and depletion									(548)	(2,107)	(2,299)
Gross profit									4,021	26,125	18,348
Advanced projects									(7,235)	(7,104)	(4,443)
Impairment of mineral property interests and property and equipment											(711)
Segment (loss) income									(3,214)	16,780	7,584
Capital expenditures										171	939
MSC
Operating Segment Reporting
Loss from investment in Minera Santa Cruz S.A.									(8,754)	(11,865)	(44)
Segment (loss) income									(8,754)	(11,865)	(44)
Los Azules
Operating Segment Reporting
Segment (loss) income									(3,411)	(7,129)	(9,221)
Total Segment
Operating Segment Reporting
Depreciation and depletion									(24,753)	(15,079)	(4,036)
Gross profit									8,986	32,082	20,080
Advanced projects									(9,520)	(15,063)	(11,129)
Loss from investment in Minera Santa Cruz S.A.									(8,754)	(11,865)	(44)
Impairment of mineral property interests and property and equipment											(711)
Segment (loss) income									(47,032)	(31,422)	(10,428)
General and Administrative and other									(16,559)	(16,218)	(15,575)
MSC
Operating Segment Reporting
Revenue from gold and silver sales									263,887	213,096	235,650
Gross profit									(33,977)	(9,117)	(31,025)
Loss before income and mining taxes									10,277	(9,607)	13,300
Gold and silver sales
Operating Segment Reporting
Revenue from gold and silver sales	$ 32,362	$ 32,691	$ 36,383	$ 15,583	$ 26,432	$ 26,896	$ 33,806	$ 41,041	117,019	128,175	67,465
Gold and silver sales \| U.S.
Operating Segment Reporting
Revenue from gold and silver sales									43,847
Gold and silver sales \| Canada
Operating Segment Reporting
Revenue from gold and silver sales									50,058	62,024	11,620
Gold and silver sales \| Mexico
Operating Segment Reporting
Revenue from gold and silver sales									23,114	66,151	55,845
Gold and silver sales \| Total Segment
Operating Segment Reporting
Revenue from gold and silver sales									117,019	128,175	67,465
Production costs applicable to sales
Operating Segment Reporting
Cost of goods and services sold									(83,280)	(81,014)	(43,349)
Production costs applicable to sales \| U.S.
Operating Segment Reporting
Cost of goods and services sold									(33,614)
Production costs applicable to sales \| Canada
Operating Segment Reporting
Cost of goods and services sold									(31,121)	(43,095)	(8,151)
Production costs applicable to sales \| Mexico
Operating Segment Reporting
Cost of goods and services sold									(18,545)	(37,919)	(35,198)
Production costs applicable to sales \| Total Segment
Operating Segment Reporting
Cost of goods and services sold									(83,280)	(81,014)	(43,349)
Exploration \| U.S.
Operating Segment Reporting
Cost of goods and services sold									(8,554)	(5,174)	(2,132)
Exploration \| Canada
Operating Segment Reporting
Cost of goods and services sold									(25,779)	(22,032)	(1,661)
Exploration \| Mexico
Operating Segment Reporting
Cost of goods and services sold										(2,241)	(5,610)
Exploration \| Los Azules
Operating Segment Reporting
Cost of goods and services sold									(3,411)	(7,129)	(9,221)
Exploration \| Total Segment
Operating Segment Reporting
Cost of goods and services sold									$ (37,744)	$ (36,576)	$ (18,624)