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INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE (Details)	3 Months Ended		6 Months Ended		3 Months Ended			6 Months Ended		12 Months Ended	1 Months Ended		3 Months Ended
	Jun. 30, 2014 USD ($)	Jun. 30, 2013 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2013 USD ($)	Jun. 30, 2014 Minera Santa Cruz S A [Member] USD ($)	Jun. 30, 2013 Minera Santa Cruz S A [Member] USD ($)	Mar. 31, 2013 Minera Santa Cruz S A [Member] USD ($)	Jun. 30, 2014 Minera Santa Cruz S A [Member] USD ($)	Jun. 30, 2013 Minera Santa Cruz S A [Member] USD ($)	Dec. 31, 2013 Minera Santa Cruz S A [Member] USD ($)	Jul. 31, 2014 Minera Santa Cruz S A [Member] Scenario Forecast [Member] USD ($)	Jul. 31, 2014 Minera Santa Cruz S A [Member] Scenario Forecast [Member] ARS	Sep. 30, 2014 Minera Santa Cruz S A [Member] Scenario Forecast [Member] USD ($)	Sep. 30, 2014 Minera Santa Cruz S A [Member] Scenario Forecast [Member] ARS	Dec. 31, 2013 Minera Santa Cruz S A [Member] Exploration Properties Located In Santa Cruz Province Argentina [Member] Vend In Agreement [Member] USD ($)
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Ownership interest (as a percent)					49.00%	49.00%		49.00%	49.00%
Income (loss) on investment in Minera Santa Cruz S.A. (net of amortization)	$ (2,438,000)	$ (1,551,000)	$ 4,591,000	$ (1,788,000)	$ (2,438,000)	$ (1,551,000)		$ 4,591,000	$ (1,788,000)
Equity method investment, overstatement of income from prior year recorded in current period							3,900,000
Entity's share of income in investee, understatement of income from prior year recorded in current period									1,900,000
Impairment of investment in MSC		95,878,000		95,878,000		95,900,000			95,900,000	95,878,000
Carrying value of properties, net of tax										35,857,000					35,900,000
Deferred tax liability related to mineral properties transferred															17,300,000
(Gain) loss on sale of assets	(18,000)	6,791,000	(18,000)	6,791,000											0
Dividends received			$ 7,113,000		$ 3,200,000	$ 0		$ 7,100,000	$ 0		$ 1,000,000	8,100,000	$ 1,000,000	8,100,000

X

- Definition

Represents the overstatement of after-tax net income, relating to the prior year, reported by an equity method investment of the entity which was deemed an immaterial error.

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No definition available.

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Represents the overstatement of the entity's proportionate share of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied related to the prior year.

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Represents the amount of the mineral property interests transferred, net of tax.

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Amount of deferred tax liability attributable to taxable temporary differences from investments (excludes investments in subsidiaries and equity method investments).

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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-Name Accounting Standards Codification

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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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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

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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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Dividends received on equity and other investments during the current period.

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