Percentage of exercise price to the fair market value of the shares covered by the stock option on the date of grant.

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Percentage of the exercise price to the fair market value of the shares covered by the stock option on the date of grant in the case of an ISO granted to a 10% stockholder.

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Represent total number of performance restricted share units awarded.

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

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Minimum period the individual is required to perform services to be fully vested under the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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

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Amount of cost expensed and capitalized for award under share-based payment arrangement.

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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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STOCK COMPENSATION PLAN (Details) - USD ($)			3 Months Ended				6 Months Ended
STOCK COMPENSATION PLAN (Details) - USD ($)	May 28, 2019	Jan. 01, 2019	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding shares			231,000		231,000		231,000
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested stock options			$ 4,800,000				$ 4,800,000
Number of shares, Granted			0	78,582	1,785		78,582
Remaining unrecognized compensation expense recognition period							2 years 3 months 10 days
Fair value of shares vested							$ 441,000
Compensation expense recognized			$ 811,000			$ 484,000	$ 1,287,000	$ 839,000
Restricted stock \| Key Personnel
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period							3 years
Restricted stock \| Non-employee directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested stock options			200,000				$ 200,000
Compensation cost related to stock awards			90,000			100,000	$ 200,000	200,000
Number of shares, Granted		38,900
Service period (in years)							3 years
Vesting period							3 years
Remaining unrecognized compensation expense recognition period							6 months
Performance-Based Restricted Stock Units (PRSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period (in years)							3 years
Number of PRSUs awarded							90,000
Compensation expense recognized			476,000			$ 358,000	$ 941,000	715,000
Equity Incentive Plan 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, shares authorized, maximum	340,000
Equity Incentive Plan 2019 \| Stock Option \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of exercise price to the fair market value							100.00%
Equity Incentive Plan 2019 \| Incentive stock options granted to any 10% stockholder \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of the exercise price to the fair market value of the shares covered by the stock option on the date of grant in the case of an ISO granted to 10% stockholder							110.00%
Equity Incentive Plan 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding shares	468,382
Number of shares expired	628,719
Compensation cost related to stock awards							$ 0	$ 0
Equity Incentive Plan 2009 \| Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested stock options			$ 0		$ 0		$ 0
Equity Incentive Plan 2009 \| Equity Incentive Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, exercise period from the grant date							10 years
Equity Incentive Plan 2009 \| Incentive stock options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, exercise period from the grant date							5 years