INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE - Summary of Operating Results from MSC (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Income taxes recovery	$ 2,656	$ 1,867
Income (loss) from investment in MSC, net of amortization	$ 190	$ 4,963
Corporate Venture
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Ownership interest (as a percent)	100.00%	100.00%
MSC
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Net sales	$ 48,343	$ 52,072
Production costs applicable to sales	(36,699)	(37,727)
Net income (loss)	$ 4,381	$ 8,728
Ownership interest (as a percent)	49.00%	49.00%
Net income (loss)	$ 2,147	$ 4,042	$ 15,961
Amortization of fair value increments	2,069	3,682	12,274
Income taxes recovery	(112)	(4,603)	$ (9,264)
Income (loss) from investment in MSC, net of amortization	$ 190	$ 4,963

Represents the amortization of fair value increments from the equity method investments.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The amount of the cost of sales reported by an equity method investment of the entity.

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The amount of net income (loss) reported by an equity method investment of the entity.

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The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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