The number of shares received for consideration.

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The amount of first year anniversary consideration

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The percentage of interest claims.

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The percentage of net royalty return.

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The amount of second year anniversary consideration

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Reduction in cash due to no longer including the former subsidiary's cash in the consolidated entity's cash.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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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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The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

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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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Property, Plant and Equipment, Net - Disposals (Details)				12 Months Ended
	Dec. 04, 2020 USD ($) shares	Jul. 20, 2020	Dec. 18, 2019 USD ($) item	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($)
Property, plant and equipment
Property, plant and equipment, net (Note 9)				$ 5,520,000	$ 6,031,000
Gain on sale of assets				525,000	3,144,000
Other operating (expense) income, net				7,000	3,238,000
Sale of Santa Maria Property \| Options Agreement
Property, plant and equipment
Gain (Loss) on sale of properties				23,000
Deferred revenue				$ 535,000
Sale of Santa Maria Property \| Fabled Copper Corp. \| Options Agreement
Property, plant and equipment
Percentage of interest claims				100.00%
Consideration Received in Shares \| shares \| shares				1,000,000
Sale of Santa Maria Property \| Fabled Copper Corp. \| Binding Letter of Intent Agreement
Property, plant and equipment
Percentage of interest claims		100.00%
Cash consideration received	$ 500,000
Consideration Received in Shares \| shares \| shares	1,000,000
First year anniversary consideration	$ 1,500,000
Second year anniversary consideration	$ 2,000,000
Percentage of royalty return	1.00%
Sale, not discontinued operations \| Penoles
Property, plant and equipment
Proceeds from sale of properties			$ 3,000,000
Number of mining concessions \| item			4
Gain on sale of assets					$ 3,000,000
Sale, not discontinued operations \| Fabled Copper Corp. \| Binding Letter of Intent Agreement
Property, plant and equipment
Consideration Received in Shares \| shares \| shares	1,000,000
Velardena Properties
Property, plant and equipment
Investment ownership percentage				100.00%