INVESTMENT IN MINERA SANTA CRUZ S.A. (“MSC”) - SAN JOSÉ MINE - Assets and Liabilities associated with MSC (Details 4) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Current assets	$ 54,443	$ 39,701
Total assets	475,085	522,958	$ 923,102
Current liabilities	22,039	24,081
Total liabilities	56,793	81,743
Impairment of investment in MSC	11,777	21,162	95,878
Depreciation expense	942	979	$ 942
MSC
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Current assets	95,300
Total assets	486,300
Current liabilities	38,800
Total liabilities	145,300
Impairment of investment in MSC	11,777	21,162
Dividend received	548	$ 9,483
MSC \| Current Period Values Excluding Fair Value Increments And Impairment Charge
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Current assets	91,100
Total assets	282,500
Current liabilities	44,400
Total liabilities	$ 79,500

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.18)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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