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INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE (Details 3) (USD $) | 12 Months Ended | 3 Months Ended | 12 Months Ended | 1 Months Ended | 3 Months Ended |  | 1 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Jun. 30, 2013 MSC | Mar. 31, 2013 MSC | Dec. 31, 2013 MSC | Oct. 31, 2013 MSC Vend-in agreement Item | Jun. 30, 2013 MSC Exploration properties in Santa Cruz, Argentina | Jun. 30, 2013 MSC Exploration properties in Santa Cruz, Argentina Minimum | Jun. 30, 2013 MSC Exploration properties in Santa Cruz, Argentina Maximum | Oct. 31, 2013 MSC Exploration properties in Santa Cruz, Argentina Vend-in agreement Item
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE |  |  |  |  |  |  |  |  |  |  |
Equity method investment, overstatement of income from prior year recorded in current period |  |  |  |  | $ 3,900,000 |  |  |  |  |  |
Entity's share of income in investee, overstatement of income from prior year recorded in current period |  |  |  |  | 1,900,000 |  |  |  |  |  |
Tax on mining real estate property (as a percent) |  |  |  |  |  |  |  | 1.00% |  |  |
Tax payable |  |  |  |  |  |  |  |  | 2,000,000 | 3,000,000 |
Impairment | 95,878,000 |  |  | 95,900,000 |  | 95,878,000 |  |  |  |  |
Deferred tax liability related to mineral properties transferred |  |  |  |  |  |  |  |  |  |  | 17,300,000
Net smelter return royalty payable (as a percent) |  |  |  |  |  |  | 2.00% |  |  |  |
Carrying value of mineral property interest | 642,968,000 | 767,067,000 | 245,454,000 |  |  |  |  |  |  |  | 53,200,000
Loss (gain) on sale of assets | $ 6,743,000 | $ (1,110,000) | $ (36,000) |  |  |  |  |  |  |  | $ 0
Area of property transferred |  |  |  |  |  |  | 82,700 |  |  |  | 48,900

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- Definition 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. + References No definition available. + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 35 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=7658923&loc=d3e32787-111569 + Details
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