The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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Amount of Net Income (Loss) attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 55
-Paragraph 4J
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-Paragraph 1A
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Dividends received on equity and other investments during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (b)
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE - Equity Method Investments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Jan. 24, 2012
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Dividends received from Minera Santa Cruz S.A	$ 17,738	$ 548	$ 9,483
Corporate Venture
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Ownership interest (as a percent)	100.00%	100.00%	100.00%
MSC
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Ownership interest (as a percent)	49.00%	49.00%	49.00%	49.00%	49.00%
Results of operations	$ 13,000	$ 2,400	$ 5,300
Dividends received from Minera Santa Cruz S.A	$ 17,700	$ 500