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Other Investments (Details) $ / shares in Units, $ in Thousands |  | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2015 shares | Mar. 31, 2015 USD ($) | Feb. 28, 2014 USD ($) | Dec. 31, 2015 USD ($) shares | Dec. 31, 2014 USD ($) shares | Mar. 31, 2015 CAD / shares shares | Mar. 31, 2015 $ / shares shares | Feb. 28, 2014 CAD / shares shares | Feb. 28, 2014 $ / shares shares
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from sale of other investments, net |  |  |  | $ 2,772 | $ 10,560 |  |  |  |
Midas Gold Corp [Member] |  |  |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |
Realized gain (loss) on other investments |  |  |  | (348) | 155 |  |  |  |
Midas Gold Shares [Member] |  |  |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |
Number of shares sold | shares |  |  |  |  |  | 8,000,000 | 8,000,000 | 16,000,000 | 16,000,000
Sale of shares (dollars per share) | (per share) |  |  |  |  |  | CAD 0.46 | $ 0.36 | CAD 0.80 | $ 0.73
Proceeds from sale of other investments, net |  | $ 2,772 | $ 10,560 | $ 2,772 | $ 10,560 |  |  |  |
Shares owned | shares | 7,802,615 |  |  | 7,802,615 | 15,802,615 | 7,802,615 | 7,802,615 | 15,802,615 | 15,802,615
Holding percentage | 4.90% | 4.90% | 11.20% |  |  |  |  |  |

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- Definition The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 + Details
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- Definition Balance held at close of period in number of shares. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-12C.Column B) -URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611225-123010 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 6 -Subparagraph (SX 210.12-14.Column B) -URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611322-123010 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-12.Column B) -URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611133-123010 + Details
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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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