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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Jan. 01, 2019
Property, Plant and Equipment [Line Items] |  |  |
Operating lease right of use asset | $ 922 | $ 0 | $ 1,140
Percentage of fair value investment | 16.50% |  |
Operating Lease, Liability | $ 1,046 |  | $ 1,230
Minimum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life (in years) |  | 3 years |
Maximum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life (in years) |  | 15 years |
Buildings |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life (in years) |  | 15 years |
Shop tools and equipment | Minimum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life (in years) | 3 years |  |
Shop tools and equipment | Maximum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life (in years) | 5 years |  |
Mining equipment |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life (in years) |  | 5 years |
Office equipment | Minimum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life (in years) | 4 years |  |
Office equipment | Maximum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life (in years) | 5 years |  |
Furniture and fixtures | Minimum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life (in years) | 5 years |  |
Furniture and fixtures | Maximum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life (in years) | 7 years |  |
Light trucks and utility vehicles |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life (in years) |  | 5 years |

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- Definition Present value of lessee's discounted obligation for lease payments from operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
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- Definition Amount of lessee's right to use underlying asset under operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
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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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- 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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