COSTS AND ESTIMATED PROFITS ON UNCOMPLETED CONTRACTS (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Schedule of costs and estimated earnings on uncompleted contracts [Abstract]
Costs incurred on uncompleted contracts	$ 29,426	$ 36,969
Estimated profits, thereon	5,259	6,711
Total	34,685	43,680
Less: billings to date	26,217	29,315
Net	8,468	14,365
Schedule of Costs and Estimated Earnings on Uncompleted Contracts Included in Condensed Consolidated Balance Sheets [Abstract]
Costs and estimated profits in excess of billings	14,415	18,459
Billings in excess of costs and estimated profits	(5,950)	(4,061)
Translation adjustment	3	(33)
Net	8,468	$ 14,365
Balances previously classified as contract liabilities at the beginning of the period that have shipped	$ 900