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EQUITY INCENTIVE PLAN (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation arrangement by share-based payment award, expiration period | 10 years |
Stock-based compensation | $ 0.7 |
Unvested stock options, unrecognized compensation expense weighted average recognition period | 1 year 8 months 12 days |
Unrecognized compensation expense related to unvested stock awards | $ 1.6 |
Stock Options [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Granted (in shares) | 433,550 | 292,604
Granted (in dollars per share) | $ 2.01 | $ 2.36
Forfeited (in shares) | (100,888) | (27,169)
Forfeited (in dollars per share) | $ 12.64 | $ 6.03
Weighted average grant date fair value (in dollars per share) | $ 1.85 |
Risk free interest rate, minimum | 0.40% |
Risk free interest rate, maximum | 1.73% |
Term | 6 years |
Stock options, expected to vest, outstanding (in shares) | 701,533 |
Stock options, expected to vest, outstanding, aggregate intrinsic value | $ 0.1 |
Stock options, expected to vest remaining contractual term | 8 years 4 months 24 days |
Minimum | Stock Options [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Volatility rate | 138.00% |
Maximum |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Stock options, unvested options, vesting period | 4 years |
Maximum | Stock Options [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Stock options, unvested options, vesting period | 4 years |
Volatility rate | 163.00% |
Equity Incentive Plan 2017 [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Number of shares authorized | 913,586 |
Shares available for grant | 90,682 |
Percentage of annual increase in number of shares authorized for grant | 5.00% |
Number of additional shares authorized | 394,905 |
Equity Incentive Plan 2017 [Member] | Stock Options [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation arrangement by share-based payment award, expiration period | 10 years |

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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Number of fully vested and expected to vest options outstanding that can 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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