XML 61 R48.htm IDEA: XBRL DOCUMENT v3.20.2
STOCK-BASED COMPENSATION - Stock-based compensation expenses (Details) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2020
Jun. 30, 2019
Jun. 30, 2020
Jun. 30, 2019
Total stock compensation expenses $ 1,361,000 $ 1,363,000 $ 2,705,365 $ 2,889,243
Research and development        
Total stock compensation expenses 528,000 593,000 1,309,000 1,280,000
General and administrative        
Total stock compensation expenses $ 833,000 $ 770,000 $ 1,396,000 $ 1,609,000