Note 20 - Business Segments - Operating Results for Business Segments (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenues	$ 145,639	$ 105,984
Operating Income (loss)	(11,368)	(33,009)
Segment Reporting, Reconciling Item, Corporate Nonsegment [Member]
Operating Income (loss)	(9,560)	(5,847)
Grid [Member]
Revenues	122,065	94,631
Grid [Member] | Operating Segments [Member]
Revenues	122,065	94,631
Operating Income (loss)	(2,754)	(24,615)
Wind [Member]
Revenues	23,574	11,353
Wind [Member] | Operating Segments [Member]
Revenues	23,574	11,353
Operating Income (loss)	$ 946	$ (2,547)