INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE - Equity Method Investments (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Corporate Venture
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Ownership interest (as a percent)	100.00%
MSC
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Ownership interest (as a percent)	49.00%
Results of operations	$ 2.3	$ 0.2
Dividends received	$ 2.0	$ 4.9

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

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Dividends received on equity and other investments during the current period.

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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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