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Note 6 - Goodwill and Indefinite-lived Intangibles - Goodwill (Details) - USD ($) $ in Thousands		3 Months Ended	9 Months Ended
	Mar. 31, 2018	Jun. 30, 2018	Sep. 30, 2018
Balance			$ 17,641
Currency translation adjustments			(135)
Goodwill impairment	$ 0	$ (1,300)	(1,263)
Balance			16,243
Power and Electromechanical Segment [Member]
Balance			13,092
Currency translation adjustments			(3)
Goodwill impairment
Balance			13,089
Energy Segment [Member]
Balance			4,549
Currency translation adjustments			(132)
Goodwill impairment			(1,263)
Balance			3,154
Other Segments [Member]
Balance
Currency translation adjustments
Goodwill impairment
Balance