STOCK BASED COMPENSATION - Restricted Stock Units (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Jan. 17, 2018
Aggregate Intrinsic Value
Stock price				$ 4.75
Stock based compensation expense	$ 30	$ 29
Restricted Stock Units
Restricted Stock Units
Vesting period	5 years
Restricted Stock Units
Restricted stock units at the beginning of the period (in shares)	165
Awarded (in shares)	5
Issued (in shares)	(40)
Restricted stock units at the end of the period (in shares)	130		165
Weighted-Average Grant Date Fair Value
Restricted stock units at the beginning of the period (in dollars per share)	$ 3.47
Awarded (in dollars per share)	8.81
Issued (in dollars per share)	1.00
Restricted stock units at the end of the period (in dollars per share)	$ 4.34		$ 3.47
Weighted Average Remaining Contractual Life
Restricted stock units	1 year 7 months 10 days		1 year 4 months 6 days
Aggregate Intrinsic Value
Restricted stock units	$ 736		$ 861
Stock price	$ 5.66		$ 5.22
Vested (in shares)	40
Restricted Stock Units | First installment
Restricted Stock Units
Vesting (as a percent)	50.00%
Restricted Stock Units | Second installment
Restricted Stock Units
Vesting (as a percent)	50.00%