INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE - Assets and Liabilities Associated with MSC (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Current assets	$ 73,114	$ 91,978
Total assets	523,626	631,223
Current liabilities	(47,827)	(48,795)
Total liabilities	(123,188)	$ (131,744)
Balance excluding FV increments \| MSC
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Current assets	86,238
Total assets	185,137
Current liabilities	(46,692)
Total liabilities	(76,759)
Adjustments \| MSC
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Current assets	1,102
Total assets	116,609
Total liabilities	(5,585)
Balance including FV increments \| MSC
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Current assets	87,340
Total assets	301,746
Current liabilities	(46,692)
Total liabilities	$ (82,344)

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 liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

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