Note 18 - Business Segments - Operating Results for Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Revenues	$ 30,254	$ 22,679
Operating Income (loss)	(5,333)	(8,869)
Corporate, Non-Segment [Member]
Operating Income (loss)	(2,713)	(1,202)
Grid [Member]
Revenues	25,737	19,829
Grid [Member] | Operating Segments [Member]
Operating Income (loss)	(1,971)	(7,281)
Wind [Member]
Revenues	4,517	2,850
Wind [Member] | Operating Segments [Member]
Operating Income (loss)	$ (649)	$ (386)