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FAIR VALUE ACCOUNTING (Details) (USD $) In Thousands, except Share data, unless otherwise specified | 3 Months Ended | 9 Months Ended |  | 12 Months Ended |  |  |  |  |  |  | 3 Months Ended
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Sep. 30, 2013 Item | Sep. 30, 2013 Item | Dec. 31, 2012 | Dec. 31, 2012 Litigation settlement agreement with respect to the Los Azules Copper Project TNR | Sep. 30, 2013 Recurring Total | Dec. 31, 2012 Recurring Total | Sep. 30, 2013 Recurring Level 1 | Dec. 31, 2012 Recurring Level 1 | Sep. 30, 2013 Recurring Level 2 | Dec. 31, 2012 Recurring Level 2 | Sep. 30, 2013 Nonrecurring Level 3 MSC Discounted cash flow Weighted Average | Sep. 30, 2013 Nonrecurring Level 3 MSC Discounted cash flow Weighted Average Argentina | Sep. 30, 2013 Nonrecurring Level 3 MSC Discounted cash flow Weighted Average United States
Assets: |  |  |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents |  |  |  |  | $ 31,062 | $ 70,921 | $ 31,062 | $ 70,921 |  |  |  |  |
IVA taxes receivable | 10,129 | 10,129 | 9,150 |  | 10,129 | 9,150 |  |  | 10,129 | 9,150 |  |  |
Assets |  |  |  |  | 41,191 | 80,071 | 31,062 | 70,921 | 10,129 | 9,150 |  |  |
Liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |
Accounts payable and accrued liabilities |  |  |  |  | 10,041 | 21,235 | 38 |  | 10,003 | 21,235 |  |  |
Litigation settlement liabilities |  |  |  |  |  | 3,830 |  | 3,830 |  |  |  |  |
Liabilities |  |  |  |  | $ 10,041 | $ 25,065 | $ 38 | $ 3,830 | $ 10,003 | $ 21,235 |  |  |
Shares of common stock required to be issued as part of settlement |  |  |  | 1,000,000 |  |  |  |  |  |  |  |  |
Number of shares of common stock required to be issued as a part of settlement |  | 15,800 |  |  |  |  |  |  |  |  |  |  |
Number of vendors to which shares of common stock are required to be issued as a part of settlement | 1 | 1 |  |  |  |  |  |  |  |  |  |  |
Discount Rate (as a percent) |  |  |  |  |  |  |  |  |  |  | 10.00% |  |
Long Term Gold Price (in dollars per ounce) |  |  |  |  |  |  |  |  |  |  | 1,300 |  |
Long Term Silver Price (in dollars per ounce) |  |  |  |  |  |  |  |  |  |  | 22.75 |  |
Inflation index (as a percent) |  |  |  |  |  |  |  |  |  |  |  | 10.00% | 1.70%

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