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FAIR VALUE ACCOUNTING (Details) (USD $) | 3 Months Ended | 6 Months Ended | 12 Months Ended | 3 Months Ended | 6 Months Ended |  |  |  | 6 Months Ended |  |  |  |  | 12 Months Ended |  |  |  |  |  |  |  |
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Jun. 30, 2014 | Jun. 30, 2013 | Jun. 30, 2014 item | Jun. 30, 2013 | Dec. 31, 2013 item | Jun. 30, 2014 Los Azules Copper Project [Member] | Jun. 30, 2014 Los Azules Copper Project [Member] | Jun. 30, 2014 Minera Santa Cruz S A [Member] | Dec. 31, 2013 Minera Santa Cruz S A [Member] | Dec. 31, 2012 Minera Santa Cruz S A [Member] | Jun. 30, 2014 Minera Santa Cruz S A [Member] Mineral Property [Member] | Jun. 30, 2014 Fair Value Measurements Recurring [Member] Estimate Of Fair Value Fair Value Disclosure [Member] | Dec. 31, 2013 Fair Value Measurements Recurring [Member] Estimate Of Fair Value Fair Value Disclosure [Member] | Jun. 30, 2014 Fair Value Measurements Recurring [Member] Fair Value Inputs Level1 [Member] | Dec. 31, 2013 Fair Value Measurements Recurring [Member] Fair Value Inputs Level1 [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Telken Tenements [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Este Tenements [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Piramides Tenements [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Tobias Tenements [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Limo Tenements [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Other United States Properties [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Minera Santa Cruz S A [Member] | Jun. 30, 2014 Fair Value Measurements Nonrecurring [Member] Estimate Of Fair Value Fair Value Disclosure [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Estimate Of Fair Value Fair Value Disclosure [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Estimate Of Fair Value Fair Value Disclosure [Member] Telken Tenements [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Estimate Of Fair Value Fair Value Disclosure [Member] Este Tenements [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Estimate Of Fair Value Fair Value Disclosure [Member] Piramides Tenements [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Estimate Of Fair Value Fair Value Disclosure [Member] Tobias Tenements [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Estimate Of Fair Value Fair Value Disclosure [Member] Limo Tenements [Member] | Jun. 30, 2014 Fair Value Measurements Nonrecurring [Member] Estimate Of Fair Value Fair Value Disclosure [Member] Los Azules Copper Project [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Estimate Of Fair Value Fair Value Disclosure [Member] Other United States Properties [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Estimate Of Fair Value Fair Value Disclosure [Member] Minera Santa Cruz S A [Member] | Jun. 30, 2014 Fair Value Measurements Nonrecurring [Member] Fair Value Inputs Level3 [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Fair Value Inputs Level3 [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Fair Value Inputs Level3 [Member] Telken Tenements [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Fair Value Inputs Level3 [Member] Este Tenements [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Fair Value Inputs Level3 [Member] Piramides Tenements [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Fair Value Inputs Level3 [Member] Tobias Tenements [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Fair Value Inputs Level3 [Member] Limo Tenements [Member] | Jun. 30, 2014 Fair Value Measurements Nonrecurring [Member] Fair Value Inputs Level3 [Member] Los Azules Copper Project [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Fair Value Inputs Level3 [Member] Other United States Properties [Member] | Dec. 31, 2013 Fair Value Measurements Nonrecurring [Member] Fair Value Inputs Level3 [Member] Minera Santa Cruz S A [Member]
Assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents |  |  |  |  |  |  |  |  |  |  |  | $ 15,149,000 | $ 24,321,000 | $ 15,149,000 | $ 24,321,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Assets |  |  |  |  |  |  |  |  |  |  |  | 15,149,000 | 24,321,000 | 15,149,000 | 24,321,000 |  |  |  |  |  |  |  |  | 310,792,000 | 262,490,000 | 26,442,000 | 5,337,000 | 9,736,000 | 11,645,000 | 23,438,000 | 310,792,000 | 9,610,000 |  | 310,792,000 | 262,490,000 | 26,442,000 | 5,337,000 | 9,736,000 | 11,645,000 | 23,438,000 | 310,792,000 | 9,610,000 |
Liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accounts payable and accrued liabilities |  |  |  |  |  |  |  |  |  |  |  | 1,093,000 | 177,000 | 1,093,000 | 177,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Liabilities |  |  |  |  |  |  |  |  |  |  |  | 1,093,000 | 177,000 | 1,093,000 | 177,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Litigation settlement liabilities | 1,100,000 |  | 1,100,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares of common stock required to be issued as a part of settlement |  |  | 379,400 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of vendors to which shares of common stock are required to be issued as a part of settlement |  |  | 1 |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investment in MSC | 210,425,000 | 212,947,000 | 210,425,000 | 212,947,000 | 212,947,000 |  |  | 210,425,000 | 212,947,000 | 273,948,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 176,282,000 |  |  |  |  |  |  |  |  |  | 176,282,000
Total Loss | $ 120,398,000 | $ 27,729,000 | $ 120,398,000 | $ 27,729,000 |  | $ 120,400,000 | $ 120,398,000 |  |  |  | $ 120,398,000 |  |  |  |  | $ 152,554,000 | $ 13,792,000 | $ 2,784,000 | $ 5,079,000 | $ 6,074,000 | $ 19,450,000 | $ 9,497,000 | $ 95,878,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash -URI http://asc.fasb.org/extlink&oid=6506951 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016 + Details
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- Definition Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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