INVESTMENT IN MINERA SANTA CRUZ S.A. (“MSC”) - SAN JOSÉ MINE - Summary of Operating Results from MSC (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Income tax recovery	$ (1,867)	$ (1,163)
(Loss) income from investment in MSC, net of amortization	4,963	329
MSC
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Net sales	52,072	45,891
Production costs applicable to sales	(37,727)	(36,863)
Net (loss) income	$ 8,248	1,232
Ownership interest (as a percent)	49.00%
Net (loss) income	$ 4,042	604	$ (2,859)
Amortization of fair value increments	(3,682)	(2,687)	(10,669)
Income tax recovery	4,603	2,412	$ 15,942
(Loss) income from investment in MSC, net of amortization	$ 4,963	$ 329

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

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee, before amortization, to which the equity method of accounting is applied.

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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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