Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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- Definition

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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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.

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- Definition

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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- Definition

The highest quantity of shares an employee can purchase under the plan per period.

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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.

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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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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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- Definition

The maximum number of shares (or other type of equity) that have been approved for issuance in the equity-based payment transaction.

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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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EQUITY INCENTIVE PLAN (Narrative) (Details) - USD ($)	1 Months Ended	3 Months Ended
EQUITY INCENTIVE PLAN (Narrative) (Details) - USD ($)	Jan. 31, 2018	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation		$ 200,000	$ 100,000
Unrecognized compensation expense related to unvested stock awards		$ 2,300,000
Unvested stock options, unrecognized compensation expense weighted average recognition period		2 years 9 months 18 days
Accrued expenses		$ 1,365,000		$ 1,583,000
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, expected to vest, outstanding (in shares)		392,398
Stock options, expected to vest, outstanding, aggregate intrinsic value		$ 0
Stock options, expected to vest remaining contractual term		9 years 4 months 24 days
Stock Options [Member] \| Performance-based milestone vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation		$ 0
Equity Incentive Plan 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares authorized	359,300
Number of shares authorized	403,744
Maximum number of shares per employee	66,666
Award plan, percentage of outstanding stock maximum	5.00%
Equity Incentive Plan 2017 [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance		44,444
Plan expiration date		Jun. 05, 2027