INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE - Summary of Operating Results from MSC (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Income taxes recovery	$ 856	$ 12,321	$ 2,723	$ 13,484
(Loss) income from investment in MSC, net of amortization	4,133	(2,652)	9,096	(2,323)
MSC
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Net sales	58,581	49,858	110,653	95,749
Production costs applicable to sales	(38,832)	(41,310)	(76,559)	(78,173)
Net (loss) income	$ 10,973	(3,042)	$ 19,221	(1,810)
Ownership interest (as a percent)	49.00%		49.00%
Net (loss) income	$ 5,377	(1,491)	$ 9,418	(887)	$ (2,859)
Amortization of fair value increments	2,774	3,401	6,456	6,088	10,669
Income taxes recovery	(1,530)	(2,240)	(6,134)	(4,652)	$ (15,942)
(Loss) income from investment in MSC, net of amortization	$ 4,133	$ (2,652)	$ 9,096	$ (2,323)

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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