5. BASIC AND DILUTED LOSS PER SHARE (Details) - shares
shares in Thousands
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Potential common stock equivalents 4,185 3,500
Stock Options [Member]    
Potential common stock equivalents 2,934 2,477
Unvested Restricted Stock [Member]    
Potential common stock equivalents 486 258
Warrants [Member]    
Potential common stock equivalents 765 765