Note 3 - Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Revenues	$ 94,038	$ 65,862	$ 188,111	$ 138,220
Grid [Member]
Revenues	76,667	54,342	152,990	114,429
Grid [Member] \| North America [Member]
Revenues	51,359	47,206	94,521	84,978
Grid [Member] \| South America [Member]
Revenues	17,406	194	39,386	442
Grid [Member] \| Asia Pacific [Member]
Revenues	5,285	4,026	9,483	22,330
Grid [Member] \| EMEA [Member]
Revenues	2,617	2,916	9,601	6,679
Wind [Member]
Revenues	17,371	11,520	35,120	23,791
Wind [Member] \| North America [Member]
Revenues	0	16	0	16
Wind [Member] \| Asia Pacific [Member]
Revenues	17,371	11,425	35,110	23,696
Wind [Member] \| EMEA [Member]
Revenues	$ 0	$ 79	$ 10	$ 79

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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+ Details