INVESTMENT IN MINERA SANTA CRUZ S.A. (''MSC'') - SAN JOSE MINE - Summary of the operating results (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Income tax recovery	$ (1,619)	$ (8,714)	$ (15,103)	$ (52,705)
(Loss) income on investment in MSC, net of amortization	(1,641)	(4,441)	(3,964)	150
MSC
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Net sales	45,357	38,263	141,106	148,386
Production costs applicable to sales	(41,767)	(36,136)	(119,940)	(117,620)
Net (loss) income	$ (3,375)	(5,488)	$ (5,185)	304
Ownership interest (as a percent)	49.00%		49.00%
Net (loss) income	$ (1,654)	(2,689)	$ (2,541)	149	$ (2,597)
Amortization of fair value increments	(1,617)	(3,522)	(7,705)	(9,652)	(13,190)
Income tax recovery	1,630	1,770	6,282	9,653	$ 10,503
(Loss) income on investment in MSC, net of amortization	$ (1,641)	$ (4,441)	$ (3,964)	$ 150

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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