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SHARE-BASED COMPENSATION - Narrative (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding (in shares)	10,227		10,227		6,236
Share-based compensation expense	$ 453	$ 229	$ 1,351	$ 911
Unrecognized compensation cost, non-vested stock options	$ 4,100		$ 4,100
Weighted-average period to recognize non-vested stock options			2 years 7 months 6 days
Weighted-average grant-date fair value of stock options granted (in dollars per share)			$ 0.56	$ 0.69
Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding (in shares)	2,100		2,100
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock available for issuance (in shares)	10,227		10,227		6,236
2014 Stock Incentive Plan \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			4 years
Period exercisable from date of grant			10 years
Stock options outstanding (in shares)	8,000		8,000
Shares of common stock available for issuance (in shares)	4,800		4,800
2009 Stock Incentive Plan \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period exercisable from date of grant			10 years
Vested stock options outstanding (in shares)			100
Vesting on the First Anniversary of Date of Grant \| 2014 Stock Incentive Plan \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, vesting rate			25.00%
Vesting at End of Each Successive Three-Month Period Thereafter \| 2014 Stock Incentive Plan \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, vesting rate			6.25%