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Segment income or loss for the period.

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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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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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The net amount of operating interest income (expense).

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Amount of investment in equity method investee and investment in and advance to affiliate.

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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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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		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Operating Segment Reporting
Revenue from gold and silver sales	$ 32,691	$ 26,896	$ 84,657	$ 101,743
Revision of estimates and accretion of reclamation obligations (note 11)	(495)	(314)	(1,383)	(896)
Depreciation and depletion	(7,488)	(3,143)	(17,501)	(10,332)
Loss from investment in Minera Santa Cruz S.A. (note 8)	(328)	(4,973)	(6,775)	(7,450)
Advanced projects	(2,140)	(5,230)	(6,881)	(10,990)
Segment income (loss)	(14,544)	(12,421)	(29,649)	(18,822)
General and Administrative and other	887	(2,482)	(7,541)	(9,950)
Gross profit	1,619	6,013	7,724	29,333
Interest and other expense	(650)	(832)	(3,946)	(612)
Revision of estimates and accretion of reclamation obligations	(495)	(314)	(1,383)	(896)
Foreign currency (loss) gain	1,616	1,159	1,242	3,568
Net income (loss)	(13,657)	(14,903)	(37,190)	(28,772)
Long-Lived Assets	550,325		550,325		$ 557,565
Investment in MSC	116,994		116,994		127,814
Mexico
Operating Segment Reporting
Depreciation and depletion	(109)	(414)	(471)	(1,819)
Advanced projects	(1,710)	(2,692)	(5,865)	(5,819)
Segment income (loss)	(732)	3,538	(1,370)	15,698
Gross profit	980	6,526	4,497	23,113
MSC
Operating Segment Reporting
Loss from investment in Minera Santa Cruz S.A. (note 8)	(328)	(4,973)	(6,775)	(7,450)
Segment income (loss)	(328)	(4,973)	(6,775)	(7,450)
Los Azules
Operating Segment Reporting
Segment income (loss)	(749)	(540)	(2,386)	(6,406)
U.S.
Operating Segment Reporting
Depreciation and depletion	(3,790)		(6,510)
Advanced projects	(46)	(2,538)	(632)	(5,171)
Segment income (loss)	(3,668)	(3,577)	(5,154)	(9,361)
Gross profit	631		1,633
Canada
Operating Segment Reporting
Depreciation and depletion	(3,589)	(2,729)	(10,520)	(8,513)
Advanced projects	(384)		(384)
Segment income (loss)	(9,067)	(6,869)	(13,964)	(11,303)
Gross profit	8	(513)	1,594	6,220
MSC
Operating Segment Reporting
Loss from investment in Minera Santa Cruz S.A. (note 8)	(328)	(4,973)	(6,775)	(7,450)
Investment in MSC	116,994		116,994		127,814	$ 150,064
Canada
Operating Segment Reporting
Revenue from gold and silver sales	11,147	11,395	36,139	46,444
Long-Lived Assets	78,770		78,770		84,119
Mexico
Operating Segment Reporting
Revenue from gold and silver sales	4,967	15,501	19,577	55,299
Long-Lived Assets	25,671		25,671		26,524
United States
Operating Segment Reporting
Revenue from gold and silver sales	16,577		28,941
Long-Lived Assets	137,400		137,400		127,617
Argentina
Operating Segment Reporting
Long-Lived Assets	308,484		308,484		319,305
Argentina \| MSC
Operating Segment Reporting
Investment in MSC	117,000		117,000		$ 127,800
Gold and silver sales
Operating Segment Reporting
Revenue from gold and silver sales	32,691	26,896	84,657	101,743
Gold and silver sales \| Mexico
Operating Segment Reporting
Revenue from gold and silver sales	4,967	15,501	19,577	55,299
Gold and silver sales \| U.S.
Operating Segment Reporting
Revenue from gold and silver sales	16,577		28,941
Gold and silver sales \| Canada
Operating Segment Reporting
Revenue from gold and silver sales	11,147	11,395	36,139	46,444
Production costs applicable to sales
Operating Segment Reporting
Cost of goods and services sold	(23,584)	(17,740)	(59,432)	(62,078)
Production costs applicable to sales \| Mexico
Operating Segment Reporting
Cost of goods and services sold	(3,878)	(8,561)	(14,609)	(30,367)
Production costs applicable to sales \| U.S.
Operating Segment Reporting
Cost of goods and services sold	(12,156)		(20,798)
Production costs applicable to sales \| Canada
Operating Segment Reporting
Cost of goods and services sold	(7,550)	(9,179)	(24,025)	(31,711)
Exploration
Operating Segment Reporting
Cost of goods and services sold	(13,695)	(8,231)	(23,717)	(29,715)
Exploration \| Mexico
Operating Segment Reporting
Cost of goods and services sold	(2)	(296)	(2)	(1,596)
Exploration \| Los Azules
Operating Segment Reporting
Cost of goods and services sold	(749)	(540)	(2,386)	(6,406)
Exploration \| U.S.
Operating Segment Reporting
Cost of goods and services sold	(4,253)	(1,039)	(6,155)	(4,190)
Exploration \| Canada
Operating Segment Reporting
Cost of goods and services sold	$ (8,691)	$ (6,356)	$ (15,174)	$ (17,523)