STOCKHOLDERS' EQUITY (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended
	Feb. 13, 2018	Mar. 31, 2018	Mar. 31, 2017
STOCKHOLDERS' EQUITY [Abstract]
Number of stock options exercised (in shares)		119,947	10,969
Common stock exercised on cashless basis (in shares)		60,372	3,039
Exercise prices of stock option (in dollars per share)		$ 4.71	$ 4.00
Underwritten public offering (in shares)	1,783,760
Public offering price per share (in dollars per share)	$ 6.75
Gross proceeds from public offering	$ 12.0
Net proceeds after underwriting discounts and commissions, and estimated expenses	$ 10.9