The carrying value of concessions allowed related to the Company’s immaterial exploration project.

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The minimum amount spend for work expenditure to withdraw the agreement.

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Total work expenditure incurred.

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The work expenditure incur for year eight.

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The work expenditure incur for year five.

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The work expenditure incur for year four.

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The work expenditure incur for year one.

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The work expenditure incur for year seven.

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The work expenditure incur for year six.

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The work expenditure incur for year three.

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The work expenditure incur for year Two.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

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The net amount of other operating income and expenses, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operations.

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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.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Property, Plant and Equipment, Net - Disposals (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		6 Months Ended
	Apr. 09, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Property, plant and equipment
Property, plant and equipment, net		$ 5,471		$ 5,471		$ 6,031
Gain on sale of assets					$ 104
Other operating (expense) income, net		$ (106)	$ 71	$ (102)	$ 179
Barrick Earn-In Agreement
Property, plant and equipment
Investment ownership percentage		30.00%		30.00%
Barrick Gold Corporation \| Barrick Earn-In Agreement
Property, plant and equipment
Total work expenditure Incur				$ 10,000
Period for work expenditure				8 years
Work expenditure incur for year one				$ 500
Work expenditure incur for year two				500
Work expenditure incur for year three				1,000
Work expenditure incur for year four				1,000
Work expenditure incur for year five				1,000
Work expenditure incur for year six				2,000
Work expenditure incur for year seven				2,000
Work expenditure incur for year eight				2,000
Minimum work expenditures spend to withdraw agreement				$ 1,000
Number of Days Notice Required to Withdraw Agreement				30 days
NewCo \| Barrick Earn-In Agreement
Property, plant and equipment
Investment ownership percentage		70.00%		70.00%
El Quevar Project \| Barrick Gold Corporation \| Barrick Earn-In Agreement
Property, plant and equipment
Investment ownership percentage	70.00%
Abelena Project
Property, plant and equipment
Carrying value of concessions allowed		$ 100
Other operating (expense) income, net		100
Equipment Leased to Other Party [Member] \| Velardena properties
Property, plant and equipment
Property, plant and equipment, net		$ 500		$ 500		$ 500
Private Placement \| Barrick Gold Corporation
Property, plant and equipment
Sale of Stock, Number of Shares Issued in Transaction	4,719,207
Sale of Stock, Price Per Share	$ 0.2119