INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE - Assets and Liabilities Associated with MSC (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Current assets	$ 59,376	$ 86,864
Total assets	616,941	592,129
Current liabilities	36,012	37,639
Total liabilities	130,995	$ 70,856
MSC
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Current assets	67,600
Total assets	336,300
Current liabilities	37,500
Total liabilities	75,500
MSC \| Current Period Values Excluding Fair Value Increments And Impairment Charge
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Current assets	67,500
Total assets	197,400
Current liabilities	42,000
Total liabilities	$ 68,100

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold, or consumed within one year (or the normal operating cycle, if longer). Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Total obligations incurred as part of normal operations that are expected to be paid during the following twelve months or within one business cycle, if longer.

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