13. INCOME TAXES (Details - Deferred tax assets) - USD ($)
$ in Thousands
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Deferred tax assets:      
Net operating loss carryforwards $ 20,583 $ 17,309  
Tax credit 1,462 1,233  
Fixed assets and intangibles 1,312 1,528  
Stock compensation 1,304 1,994  
Accruals and other 218 212  
Lease liability 33  
Total deferred tax assets 24,912 22,276  
Deferred tax liabilities:      
Right of use asset (35) 0  
Total deferred tax assets (35) 0  
Valuation allowance (24,877) (22,276) $ (19,497)
Net deferred tax asset $ 0 $ 0