Business and Summary of Significant Accounting Policies (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2017	Jul. 12, 2017	Apr. 26, 2017
Accounting Policies [Abstract]
Stock issued for all issued and outstanding shares of acquisition company at .3572 shares per 1 share		19,788,177
Stock options granted to acquired option holders		1,782,428
Total purchase price of acquisition	$ 16,110
Stock issuance costs	$ 117
Percentage ownership Florida Canyon zinc project	39.00%
Percent ownership in Lik zinc deposit	50.00%
Zazu convertible debenture at 5% per annum			$ 1,500
Zazu debenture convertible price per share			$ 0.22
Cash and cash equivalents held in brokerage accounts and foreign banks	$ 168
Current assets in United States Treasury securities	10,395
Bank certificates of deposit each with $250,000 maximum	$ 1,247
Potentially dilutive shares related to outstanding common stock options	1,982,428

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The capitalized costs incurred during the period (excluded from amortization) to purchase, lease or otherwise acquire an unproved property, including costs of lease bonuses and options to purchase or lease properties, the portion of costs applicable to minerals when land including mineral rights is purchased in fee, brokers' fees, recording fees, legal costs, and other costs incurred in acquiring properties.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-10(c)(7)(ii))
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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section 50
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A savings certificate entitling the Entity (that is, bearer) to receive interest at an established maturity date, based upon a fixed interest rate. A certificate of deposit may be issued in any denomination. Certificates of deposit are generally issued by commercial banks and, therefore, insured by the FDIC (up to the prescribed limit). Certificates of deposit generally restrict holders from withdrawing funds on demand without the incurrence of penalties. Generally, only certificates of deposit with original maturities of three months or less qualify as cash equivalents. Original maturity means original maturity to the entity holding the investment. As a related example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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The price per share of the conversion feature embedded in the debt instrument.

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-Name Accounting Standards Codification
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