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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)	12 Months Ended
	Dec. 31, 2016
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 & utility vehicles
Property, Plant and Equipment [Line Items]
Useful life (in years)	5 years
Nichols Ranch Project
Property, Plant and Equipment [Line Items]
Useful life (in years)	12 years
Alta Mesa
Property, Plant and Equipment [Line Items]
Useful life (in years)	15 years

X

- 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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