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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Tangible Assets (Details) | 12 Months Ended
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Dec. 31, 2019
Preparation plants, processing facilities and mineral rights | Minimum |
Property, Plant and Equipment |
Estimated useful life | 1 year
Preparation plants, processing facilities and mineral rights | Maximum |
Property, Plant and Equipment |
Estimated useful life | 28 years
Other plant and equipment and mining equipment | Minimum |
Property, Plant and Equipment |
Estimated useful life | 1 year
Other plant and equipment and mining equipment | Maximum |
Property, Plant and Equipment |
Estimated useful life | 28 years
Buildings, office equipment and improvements | Minimum |
Property, Plant and Equipment |
Estimated useful life | 1 year
Buildings, office equipment and improvements | Maximum |
Property, Plant and Equipment |
Estimated useful life | 25 years

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- Definition 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. + References No definition available. + Details
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Period Type: | duration

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- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
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- Details
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- Details
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- Details
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- Details
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- Details
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