STOCKHOLDERS' EQUITY AND STOCK-BASED COMPENSATION - Stock Options Activity (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Number of Options
Outstanding, Beginning Balance, Number of Options	75,062	142,502
Granted, Number of Options
Exercised, Number of Options	(41,310)	(67,440)
Expired/Forfeited, Number of Options	(502)
Outstanding, Ending Balance, Number of Options	33,250	75,062
Weighted Average Exercise Price
Outstanding, Beginning Balance, Weighted Average Exercise Price	$ 7.95	$ 8.19
Granted, Weighted Average Exercise Price
Exercised, Weighted Average Exercise Price	6.62	8.45
Expired/Forfeited, Weighted Average Exercise Price	6.00
Outstanding, Ending Balance, Weighted Average Exercise Price	$ 9.64	$ 7.95
Additional information
Options Outstanding, Weighted Average Remaining Contractual Term	10 months 24 days
Options exercisable at end of year (in shares)	33,250	75,062
Options exercisable at end of year, Weighted Average Exercise Price	$ 9.64	$ 7.95
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized under plan	1,650,000
Shares available for grant	364,928
Number of Options
Granted, Number of Options	0	0
Additional information
Weighted average remaining contractual term	4 months 24 days
Grant date fair value of options outstanding and exercisable	$ 148,000	$ 224,000
Fair value of options exercised	75,000	183,000
Total intrinsic value of options exercised	$ 313,000	$ 494,000

Fair value of options exercised

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Fair value as of their grant date of options outstanding and exercisable at period end.

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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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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 into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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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 vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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