STOCK BASED COMPENSATION (Details - Compensation Expense) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2021 |
Jun. 30, 2020 |
Jun. 30, 2021 |
Jun. 30, 2020 |
|
| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||||
| Allocated stock-based compensation | $ 847 | $ 766 | $ 1,578 | $ 1,395 |
| Research and Development Expense [Member] | ||||
| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||||
| Allocated stock-based compensation | 267 | 297 | 490 | 524 |
| General and Administrative Expense [Member] | ||||
| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||||
| Allocated stock-based compensation | 554 | 430 | 1,009 | 799 |
| Selling and Marketing [Member] | ||||
| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||||
| Allocated stock-based compensation | $ 26 | $ 39 | $ 79 | $ 72 |