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OPERATING SEGMENT REPORTING (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018 | Dec. 31, 2017
Operating Segment Reporting |  |  |  |
Revenues | $ 15,640 | $ 41,285 | $ 41,285 |
Revision of estimates and accretion of reclamation obligations | (461) | (294) |  |
Property holding costs | (1,608) | (1,411) |  |
General and administrative expenses | (3,871) | (5,187) |  |
(Loss) from investment in Minera Santa Cruz S.A. (net of amortization) | (2,310) | (212) |  |
Interest and other expense | (513) | (134) |  |
Revision of estimates and accretion of reclamation obligations | (461) | (294) |  |
Foreign currency gain | 163 | 927 |  |
Net (loss) income before tax | (10,018) | (6,349) |  |
Long-Lived Assets | 563,316 |  | 557,565 |
Investment in MSC | 123,484 |  | 127,814 |
Mexico |  |  |  |
Operating Segment Reporting |  |  |  |
Property holding costs | (1,197) | (1,149) |  |
General and administrative expenses | (1,202) | (829) |  |
Segment income (loss) | (1,302) | 8,480 |  |
MSC |  |  |  |
Operating Segment Reporting |  |  |  |
(Loss) from investment in Minera Santa Cruz S.A. (net of amortization) | (2,310) | (212) |  |
Segment income (loss) | (2,310) | (212) |  |
Los Azules |  |  |  |
Operating Segment Reporting |  |  |  |
Property holding costs | (20) | (40) |  |
General and administrative expenses | (184) | (278) |  |
Segment income (loss) | (1,117) | (3,525) |  |
U.S. |  |  |  |
Operating Segment Reporting |  |  |  |
Property holding costs | (341) | (179) |  |
General and administrative expenses | (195) | (863) |  |
Segment income (loss) | (869) | (3,042) |  |
Canada |  |  |  |
Operating Segment Reporting |  |  |  |
Property holding costs | (50) | (43) |  |
General and administrative expenses | (28) | (88) |  |
Segment income (loss) | (2,022) | (2,325) |  |
Total Segment |  |  |  |
Operating Segment Reporting |  |  |  |
Property holding costs | (1,608) | (1,411) |  |
General and administrative expenses | (1,609) | (2,058) |  |
(Loss) from investment in Minera Santa Cruz S.A. (net of amortization) | (2,310) | (212) |  |
Segment income (loss) | (7,620) | (624) |  |
Corporate & Other |  |  |  |
Operating Segment Reporting |  |  |  |
Revision of estimates and accretion of reclamation obligations | (461) | (294) |  |
General and administrative expenses | (2,262) | (3,129) |  |
Depreciation | (152) | (360) |  |
Interest and other expense | (513) | 134 |  |
Revision of estimates and accretion of reclamation obligations | (461) | (294) |  |
Gain (loss) on sale of marketable equity securities (note 2) | 827 | (2,735) |  |
Foreign currency gain | 163 | 927 |  |
MSC |  |  |  |
Operating Segment Reporting |  |  |  |
(Loss) from investment in Minera Santa Cruz S.A. (net of amortization) | (2,310) | (212) |  |
Investment in MSC | 123,484 |  | 127,814 | $ 150,064
Canada |  |  |  |
Operating Segment Reporting |  |  |  |
Revenues | 8,943 |  | 15,868 |
Long-Lived Assets | 83,798 |  | 84,119 |
Mexico |  |  |  |
Operating Segment Reporting |  |  |  |
Revenues | 5,798 |  | 25,417 |
Long-Lived Assets | 25,873 |  | 26,524 |
United States |  |  |  |
Operating Segment Reporting |  |  |  |
Revenues | 899 |  |  |
Long-Lived Assets | 138,670 |  | 127,617 |
Argentina |  |  |  |
Operating Segment Reporting |  |  |  |
Long-Lived Assets | 314,975 |  | 319,305 |
Argentina | MSC |  |  |  |
Operating Segment Reporting |  |  |  |
Investment in MSC | 123,500 |  | $ 127,800 |
Gold and silver sales |  |  |  |
Operating Segment Reporting |  |  |  |
Revenues | 15,583 | 41,041 |  |
Gold and silver sales | Mexico |  |  |  |
Operating Segment Reporting |  |  |  |
Revenues | 5,798 | 25,417 |  |
Gold and silver sales | U.S. |  |  |  |
Operating Segment Reporting |  |  |  |
Revenues | 842 |  |  |
Gold and silver sales | Canada |  |  |  |
Operating Segment Reporting |  |  |  |
Revenues | 8,943 | 15,624 |  |
Gold and silver sales | Total Segment |  |  |  |
Operating Segment Reporting |  |  |  |
Revenues | 15,583 | 41,041 |  |
Other revenue |  |  |  |
Operating Segment Reporting |  |  |  |
Revenues | 57 | 244 |  |
Other revenue | U.S. |  |  |  |
Operating Segment Reporting |  |  |  |
Revenues | 57 |  |  |
Other revenue | Canada |  |  |  |
Operating Segment Reporting |  |  |  |
Revenues |  | 244 |  |
Other revenue | Total Segment |  |  |  |
Operating Segment Reporting |  |  |  |
Revenues | 57 |  |  |
Production costs applicable to sales |  |  |  |
Operating Segment Reporting |  |  |  |
Cost of goods and services sold | (13,168) | (26,394) |  |
Production costs applicable to sales | Mexico |  |  |  |
Operating Segment Reporting |  |  |  |
Cost of goods and services sold | (3,925) | (13,608) |  |
Production costs applicable to sales | U.S. |  |  |  |
Operating Segment Reporting |  |  |  |
Cost of goods and services sold | (748) |  |  |
Production costs applicable to sales | Canada |  |  |  |
Operating Segment Reporting |  |  |  |
Cost of goods and services sold | (8,495) | (12,786) |  |
Production costs applicable to sales | Total Segment |  |  |  |
Operating Segment Reporting |  |  |  |
Cost of goods and services sold | (13,168) | (26,394) |  |
Mine development |  |  |  |
Operating Segment Reporting |  |  |  |
Cost of goods and services sold | (776) | (380) |  |
Mine development | Mexico |  |  |  |
Operating Segment Reporting |  |  |  |
Cost of goods and services sold | (776) | (380) |  |
Mine development | Total Segment |  |  |  |
Operating Segment Reporting |  |  |  |
Cost of goods and services sold | (776) | (380) |  |
Exploration |  |  |  |
Operating Segment Reporting |  |  |  |
Cost of goods and services sold | (3,789) | (11,454) |  |
Exploration | Mexico |  |  |  |
Operating Segment Reporting |  |  |  |
Cost of goods and services sold |  | (971) |  |
Exploration | Los Azules |  |  |  |
Operating Segment Reporting |  |  |  |
Cost of goods and services sold | (913) | (3,207) |  |
Exploration | U.S. |  |  |  |
Operating Segment Reporting |  |  |  |
Cost of goods and services sold | (484) | (2,000) |  |
Exploration | Canada |  |  |  |
Operating Segment Reporting |  |  |  |
Cost of goods and services sold | (2,392) | (5,276) |  |
Exploration | Total Segment |  |  |  |
Operating Segment Reporting |  |  |  |
Cost of goods and services sold | $ (3,789) | $ (11,454) |  |

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