Number of options awarded in lieu of bonus in cash.

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Fair value of options granted in period. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Number of options awarded with performance conditions for vesting.

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Intrinsic value of warrants outstanding.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Aggregate number of common shares reserved for future issuance.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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Net number of non-option equity instruments granted to participants.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of options outstanding, including both vested and non-vested options.

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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Equity - Equity Incentive Plan (Details) - USD ($)			3 Months Ended			6 Months Ended		12 Months Ended
Equity - Equity Incentive Plan (Details) - USD ($)	Jul. 28, 2021	Jan. 22, 2021	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Share-based compensation
Warrants Intrinsic Value Outstanding			$ 8,100,000			$ 8,100,000
Stock grants	17,000	62,500		79,500
Exercise price (in dollars per share)	$ 4.15	$ 3.97
Non-vested stock options
Share-based compensation
Allocated Share-based Compensation Expense			0		$ 13,000	$ 13,000	$ 26,000
Contractual life						10 years
Fair value of options granted (in dollars)						$ 176,000
Minimum [Member] \| Non-vested stock options
Share-based compensation
Exercise price (in dollars per share)						$ 1.16
Restricted Stock Units \| 2021 Director Awards
Share-based compensation
Fair value of the RSUs aggregate			$ 84,000
Equity Incentive Plan [Member]
Share-based compensation
Number of common stock reserved for issuance			3,125,466			3,125,466
Reserved			885,000			885,000
Reserved but unissued shares under the Consultant Plan at Period End			885,000			885,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number			2,518,403			2,518,403		2,379,752
Allocated Share-based Compensation Expense			$ 19,000		$ 48,000	$ 429,000	$ 115,000
Contractual life						10 years
Equity Incentive Plan [Member] \| Non-vested stock options
Share-based compensation
Share-based Compensation Outstanding - Reserved but unissued shares under the Plan			3,309,651			3,309,651		2,697,119
Equity Incentive Plan [Member] \| Board of Directors [Member]
Share-based compensation
Stock grants			52,000		34,000	262,000	87,000
Equity Incentive Plan [Member] \| 2021 Employee Awards
Share-based compensation
Allocated Share-based Compensation Expense								$ 192,000
Fair value of options granted (in dollars)						$ 1,900,000
Stock options issued in lieu of bonus in cash								80,000
Number of options awarded with performance condition						805,000
Equity Incentive Plan [Member] \| 2021 Director Awards
Share-based compensation
Allocated Share-based Compensation Expense								$ 217,000
Exercise price (in dollars per share)						$ 3.37
Stock options issued in lieu of bonus in cash						64,439
Equity Incentive Plan [Member] \| Performance Incentive Awards, Probable [Member]
Share-based compensation
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized			$ 182,000			$ 182,000
Equity Incentive Plan [Member] \| Performance Incentive Awards, Not Probable [Member]
Share-based compensation
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized			$ 1,300,000			$ 1,300,000
Unrecognized compensation expense period for recognition						1 year
2021 Plan
Share-based compensation
Number of common stock reserved for issuance			3,381,369			3,381,369