SUPPLEMENTAL CASH FLOW INFORMATION (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Non-cash investing and financing activities:
Purchase of property, plant, and equipment in accounts payable	$ 3,375	$ 4,430	$ 2,389
Additional cash payment information:
Interest paid	2,212	1,611	1,578
Income taxes paid	$ 10,566	$ 7,111	$ 8,818