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STOCK OPTIONS - Narrative (Details) - USD ($) $ in Thousands		12 Months Ended
	Jun. 01, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, nonvested options		$ 2,069
Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term	10 years
Unrecognized compensation cost, nonvested options, period for recognition		3 years 5 months 8 days
Restricted Stock \| Minimum \| Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		5 years
2015 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares permitted for grant (in shares)		1,000,000
2015 Equity Incentive Plan \| Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term		10 years
Share-based compensation expense		$ 663	$ 592	$ 355
2015 Equity Incentive Plan \| Option \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		5 years
2015 Equity Incentive Plan \| Option \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		10 years