INVESTMENT IN MINERA SANTA CRUZ S.A. (''MSC'') - SAN JOSE MINE (Details 4) (USD $) In Thousands, unless otherwise specified	9 Months Ended			3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2013	Sep. 30, 2014	Dec. 31, 2013	Jun. 30, 2013 MSC	Sep. 30, 2013 MSC	Dec. 31, 2013 MSC	Sep. 30, 2014 MSC	Jun. 30, 2014 MSC Current Period Values Excluding Fair Value Increments And Impairment Charge
INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE
Current assets		$ 39,702	$ 46,771				$ 98,300	$ 101,200
Total assets		783,460	923,066				518,500	308,900
Current liabilities		19,768	11,189				56,900	56,900
Total liabilities		132,622	176,299				141,600	94,500
Impairment of investment in MSC	$ 95,878			$ 95,900	$ 95,900	$ 95,878

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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