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Fair Value of Financial Instruments (Details) In Thousands, except Per Share data, unless otherwise specified |  |  |  |  |  |  | 6 Months Ended
--- | --- | --- | --- | --- | --- | --- | ---
Jun. 30, 2012 USD ($) | Apr. 18, 2012 USD ($) | Mar. 13, 2012 CAD | Dec. 31, 2011 USD ($) | Apr. 20, 2011 USD ($) | Apr. 20, 2011 CAD | Jun. 30, 2012 Fair Value, Inputs, Level 1 [Member] USD ($) | Jun. 30, 2012 Fair Value, Inputs, Level 3 [Member] USD ($) | Jun. 30, 2012 Maximum [Member] Fair Value, Inputs, Level 3 [Member] | Jun. 30, 2012 Minimum [Member] Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |  |  |  |  |  |  |  |  |
Quoted market price of Midas Gold Shares (in dollars per share) |  | $ 2.30 | 3.30 |  | $ 3.43 | 3.30 | $ 2.44 |  |  |
Amayapampa interest | $ 4,813 |  |  | $ 4,813 |  |  |  | $ 4,813 |  |
Weighted average gold price per ounce (in dollars per ounce) |  |  |  |  |  |  |  | 1,150 |  |
Estimated gold production (in ounces) |  |  |  |  |  |  |  |  | 650,000 | 350,000
Timing of commencement of commercial production |  |  |  |  |  |  |  |  | 7 years | 2 years

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- Definition The aggregate value (measured at the lower of net carrying value or fair value less cost of disposal) for noncurrent assets (assets with expected useful life longer than one year or one operating cycle, whichever is longer) of a disposal group, including a component of the entity (discontinued operation), to be sold or that has subsequently been disposed of through sale, as of the financial statement date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 144 -Paragraph 46 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition Price of a single share of a number of saleable stocks of a company. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 + Details
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- Definition The amount of estimated gold production, used as an input to measure fair value. + References No definition available. + Details
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- Definition Price per ounce, used as an input to measure fair value. + References No definition available. + Details
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- Definition The estimated time period that gold production will commence, used as an input to measure fair value. + References No definition available. + Details
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