Aggregate value of securities allowed under offering agreement.

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Aggregate number of securities allowed under offering agreement.

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Common Stock Available For Future Issuance

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Represents the percentage of underwriting discount related to the issuance of equity.

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Percentage of commission on the gross sales price per share of common stock sold.

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Represents the percentage of placement agent fee.

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The remaining balance of equity issuance expenses that were capitalized and are being amortized against equity.

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The exercisable period of warrant from the date of issuance.

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The amount of warrant issued during period

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The amount of amortization of deferred charges applied against earnings during the period.

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Exercise price per share or per unit of warrants or rights outstanding.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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The cash outflow for cost incurred directly with the issuance of an equity security.

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The cash inflow from the additional capital contribution to the entity.

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The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

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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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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Price of a single share of a number of saleable stocks of a company.

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Per share or per unit amount of equity securities issued.

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Number of new stock issued during the period.

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Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Equity - Issue and Conversion (Details) - USD ($)						1 Months Ended	3 Months Ended	6 Months Ended
Equity - Issue and Conversion (Details) - USD ($)	Jul. 21, 2020	Apr. 22, 2020	Apr. 20, 2020	Apr. 09, 2020	Jul. 17, 2019	Dec. 31, 2016	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	May 09, 2018
Proceeds from issuance of common stock, net of issuance costs								$ 2,714,000	$ 4,079,000
Warrants Series A and B
Exercise price			$ 0.24
Warrants issued			$ 1,900,000
Expected volatility (as a percent)			95.00%
Risk-free rate (as a percent)			0.41%
Series B Warrants
Warrants Exercise Period					6 months
Private Placement
Total cost of offering			$ 334,000
Placement agent fee (as a percent)			6.00%
Private Placement \| Warrants Series A and B
Share Price			$ 0.30
Aggregate gross proceeds of warrants			$ 3,000,000.0
ATM Agreement
Proceeds from issuance of common stock, net of issuance costs								$ 1,800,000	$ 223,000
Stock Issued During period Shares New Issues								1,856,960	823,452
Aggregate value of securities allowed under agreement						$ 5,000,000.0
Sale price (in dollars per shares)							$ 0.28	$ 0.97	$ 0.28
Amortization of deferred cost								$ 57,000	$ 8,000
Unamortized deferred cost							$ 129,000	$ 71,000	$ 129,000
Aggregate securities allowed under agreement (in shares)						10,000,000
Commission rate (as a percent)						2.00%
common shares available for issuance								2,200,000
LPC Program [Member]
Proceeds from issuance of common stock, net of issuance costs								$ 216,000
Stock Issued During period Shares New Issues								900,000
Sale price (in dollars per shares)								$ 0.27
Amortization of deferred cost								$ 24,000
Unamortized deferred cost								$ 353,000
Commitment purchase agreement
Aggregate value of securities allowed under agreement										$ 10,000,000.0
Firm Commitment Offering
Number of shares to purchase in agreement	17,857,143
Purchase price	$ 0.42
Percentage of underwriting discount	6.00%
Total cost of offering	$ 155,000
Proceeds from issuance of common stock, net of issuance costs	$ 8,000,000.0
Over-Allotment Option
Number of shares to purchase in agreement	2,678,571
Minimum \| Private Placement
Warrants Exercise Period		6 months
Maximum \| Private Placement
Expiration term of warrant		5 years
Common Stock \| Private Placement
Stock Issued During period Shares New Issues			15,000,000				15,000,000
Share Price			$ 0.20
Common shares issuable upon exercise			11,250,000
Common Stock \| Private Placement \| Series A Warrants
Common shares issuable upon exercise			7,500,000
Common Stock \| Private Placement \| Series B Warrants
Common shares issuable upon exercise			3,750,000
Exercise price		$ 0.26
Common Stock \| Subscription Agreement
Stock Issued During period Shares New Issues							4,719,207
Barrick \| Subscription Agreement
Number of shares to purchase in agreement				4,719,207
Purchase price				$ 0.2119
Proceeds from issuance of common stock, net of issuance costs				$ 900,000