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INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE (Details 2) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 8 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Sep. 30, 2013 | Jun. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Dec. 31, 2012
Change in the investment in MSC |  |  |  |  |  |  |
Investment in MSC, beginning of period |  |  |  |  | $ 273,948 |  |
Impairment of investment in MSC |  |  |  |  | (95,878) |  |
Investment in MSC, end of period | 177,080 |  |  |  | 177,080 |  |
MSC |  |  |  |  |  |  |
Change in the investment in MSC |  |  |  |  |  |  |
Investment in MSC, beginning of period |  |  |  |  | 273,948 |  |
Fair value of investment in MSC from acquisition of Minera Andes |  |  | 261,200 | 261,200 |  | 261,200 | 262,883
Income from equity investment | 2,658 |  | 12,908 | 18,505 | 3,914 |  | 25,301
Amortization of fair value increments | (618) |  | (1,668) | (3,537) | (3,662) | (3,537) | (4,466)
Dividend distribution |  |  |  |  | (1,242) |  | (9,770)
Impairment of investment in MSC |  | (95,900) |  |  | (95,878) |  |
Investment in MSC, end of period | $ 177,080 |  |  |  | $ 177,080 |  | $ 273,948

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