13. INCOME TAXES (Details - Unrecognized tax benefits) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Income Tax Disclosure [Abstract]    
Unrecognized tax benefit, beginning balance $ 732 $ 606
Increase - prior year tax position 4
Increase - current year tax position 133 122
Unrecognized tax benefit, ending balance $ 865 $ 732