STOCKHOLDERS' EQUITY - Restricted Stock (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Restricted Stock
Vested (in shares)		(43,397)	(4,444)
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized
Stock-based compensation	$ 5,842	$ 6,196	$ 2,603
Restricted stock
Restricted Stock
Outstanding at period start (in shares)	436,730	318,002	177,293
Granted (in shares)	114,256	164,010	154,769
Forfeited (in shares)	(6,354)	(1,885)	(9,616)
Vested (in shares)	(176,186)
Outstanding at period end (in shares)	368,446	436,730	318,002	177,293
Restricted stock exercisable (in shares)	0
Weighted-Average Remaining Contractual Terms (in Years)
Weighted-average remaining contractual terms (in years)	1 year 1 month 6 days	1 year 1 month 6 days	1 year 8 months 12 days	2 years 2 months 12 days
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized
Unrecognized compensation expense	$ 7,075
Unrecognized compensation expense, weighted average period of recognition	1 year 1 month 6 days
Stock-based compensation expense	$ 5,842	$ 6,196	$ 2,603
Restricted stock \| Executive Officer
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized
Stock-based compensation	$ 1,542

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

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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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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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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