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GOODWILL AND INTANGIBLE ASSETS (Details) - USD ($) $ in Thousands		3 Months Ended	12 Months Ended
	Oct. 01, 2019	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill
Goodwill impairment			$ 3,279	$ 0	$ 0
Goodwill		$ 60,691	60,691	63,970	63,970
Impairment of goodwill and intangible assets	$ 0
Viya (formerly Innovative)
Goodwill
Goodwill		$ 20,600	$ 20,600
Amount by which fair value exceeded its carrying value		12.00%	12.00%
Renewable Energy
Goodwill
Goodwill impairment		$ 3,300	$ 3,279
Goodwill		$ 0	$ 0	$ 3,279	$ 3,279