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Note 5 - Goodwill and Indefinite-lived Intangibles - Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended			12 Months Ended
	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Balance				$ 0	$ 4,549
Currency translation adjustments					(202)
Goodwill impairment	$ (3,100)	$ (1,300)	$ (3,200)		(4,347)	$ (3,152)
Balance	0		4,549	0	0	4,549
Energy Segment [Member]
Balance					4,549
Currency translation adjustments					(202)
Goodwill impairment					(4,347)
Balance			4,549			4,549
Other Segments [Member]
Balance
Currency translation adjustments
Goodwill impairment
Balance