SUPPLEMENTAL CASH FLOW INFORMATION (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
SUPPLEMENTAL CASH FLOW INFORMATION [Abstract]
Interest paid	$ 118	$ 82
Federal, state, and local income taxes paid, net	7	5,326
Change in contract receivables, net	3,492	(1,959)
Change in contract liabilities, net	(3,492)	1,959
Property, plant, and equipment purchases in accounts payable	$ 462	$ 741