INVESTMENT IN MINERA SANTA CRUZ S.A. (''MSC'') - SAN JOSE MINE (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Income on investment in MSC, net of amortization	$ 7,029	$ (237)
MSC
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Net sales percentage	100.00%	100.00%
Net sales	56,889	43,813
Production costs applicable to sales	(39,637)	(36,803)
Income from operations before extraordinary items	6,182	2,440
Net income	6,182	2,440
Ownership interest (as a percent)	49.00%	49.00%
Net income on investment in MSC	3,029	1,196	2,126
Amortization of fair value increments, net of tax	4,000	(1,433)	(1,280)
Income on investment in MSC, net of amortization	$ 7,029	$ (237)

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

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Represents the revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity expressed as percentage.

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No definition available.

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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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No definition available.

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- Definition

The amount of income (loss) from continuing operations before extraordinary items 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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No definition available.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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