EQUITY INCENTIVE PLAN (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 0.4	$ 0.2
Unvested stock options, unrecognized compensation expense weighted average recognition period	2 years 2 months 12 days
Unrecognized compensation expense related to unvested stock awards	$ 2.3
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	591,097	325,050
Granted (in dollars per share)	$ 2.16	$ 2.09
Forfeited (in shares)	(55,993)	(13,267)
Forfeited (in dollars per share)	$ 2.25	$ 5.43
Stock options, expected to vest, outstanding (in shares)	1,133,868
Stock options, expected to vest, outstanding, aggregate intrinsic value	$ 0.2
Stock options, expected to vest remaining contractual term	8 years 9 months 18 days
Equity Incentive Plan 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	1,792,431
Shares available for grant	434,423
Percentage of annual increase in number of shares authorized for grant	5.00%
Number of additional shares authorized	878,845
Equity Incentive Plan 2017 [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Plan expiration date	Jun. 05, 2027

Percentage of annual increase in number of shares authorized for grant

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

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Amount of cost to be recognized for option under share-based payment arrangement.

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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.

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Date the equity-based award expires, in CCYY-MM-DD format.

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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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Number of additional shares authorized for issuance under share-based payment arrangement.

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Number of shares authorized for issuance under share-based payment arrangement.

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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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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.

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Gross number of share options (or share units) granted during the period.

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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.

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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.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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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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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. 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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