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Other Investments (Summary) (Details) - USD ($) $ in Thousands | 1 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2015 | Feb. 28, 2014 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Sale of Midas Gold Shares, net of costs to sell |  |  |  | $ (2,772) | $ (10,560)
Gain/(loss) during the period |  |  | $ 3,196 | (1,593) | (4,112)
Midas Gold Shares [Member] |  |  |  |  |
Fair value at beginning of period |  |  | 1,798 | 6,163 |
Sale of Midas Gold Shares, net of costs to sell | $ (2,772) | $ (10,560) |  | (2,772) |
Gain/(loss) during the period |  |  | 3,196 | (1,593) |
Fair value at end of period |  |  | $ 4,994 | $ 1,798 | $ 6,163
Midas Gold Shares held at end of the period | 7,802,615 | 15,802,615 | 7,802,615 | 7,802,615 |

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- Definition The cash inflow associated with the sale of other investments not otherwise defined in the taxonomy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3179-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3521-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 26 -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3574-108585 + Details
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