STOCK-BASED COMPENSATION (Equity Based Compensation Schedule) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Allocation of stock-based compensation expense
Stock compensation expense	$ 5,262	$ 4,121
Research and development
Allocation of stock-based compensation expense
Stock compensation expense	2,556	2,118
Research and development | Employees
Allocation of stock-based compensation expense
Stock compensation expense	2,479	1,937
Research and development | Non-employees
Allocation of stock-based compensation expense
Stock compensation expense	77	181
Sales, marketing and administration
Allocation of stock-based compensation expense
Stock compensation expense	2,706	2,003
Sales, marketing and administration | Non-employees
Allocation of stock-based compensation expense
Stock compensation expense	102	179
Sales, marketing and administration | Employees and directors
Allocation of stock-based compensation expense
Stock compensation expense	$ 2,604	$ 1,824