REVENUE FROM CONTRACTS WITH CUSTOMERS (Details - Contract balances) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Costs incurred on uncompleted contracts	$ 3,293	$ 2,098
Estimated earnings on uncompleted contracts	4,021	3,153
Gross costs and estimated earnings	7,314	5,251
Less: Billings to date on uncompleted contracts	(6,985)	(5,792)
Costs incurred plus estimated earning less billings on uncompleted contracts	329	(541)
Included in the accompanying unaudited condensed consolidated balance sheets under the following captions:
Contract assets	502	189
Contract liabilities	$ (173)	$ (730)