STOCK BASED COMPENSATION - Stock Options (Details) - Stock Options - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Stock Options
Expiration period	10 years
Shares
Options outstanding at the beginning of the period (in shares)	7
Exercised (in shares)	(4)
Options outstanding at the end of the period (in share)	3	7
Options exercisable at the end of the period (in shares)	3
Weighted Average Exercise Price
Options outstanding at the beginning of the period (in dollars per share)	$ 4.12
Exercised (in dollars per share)	1.56
Options outstanding at the end of the period (in dollars per share)	7.40	$ 4.12
Options exercisable at the end of the period (in dollars per share)	$ 7.40
Weighted Average Remaining Contractual Life
Options outstanding	9 years 1 month 2 days	4 years 5 months 16 days
Options exercisable	9 years 1 month 2 days
Aggregate Intrinsic value of options outstanding		$ 15
Stock price	$ 4.02	$ 5.22