Note 7 - Property, Plant, and Equipment, Net - Schedule of Property, Plant, Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Mar. 31, 2025
Total property, plant, and equipment	$ 42,291	$ 32,380
Less: accumulated depreciation	(2,614)	(1,435)
Total property, plant, and equipment, net	39,677	30,945
Fiber Plant [Member]
Total property, plant, and equipment	29,835	21,375
Equipment [Member]
Total property, plant, and equipment	10,669	9,794
Leasehold Improvements [Member]
Total property, plant, and equipment	592	580
Furniture and Fixtures [Member]
Total property, plant, and equipment	281	249
Tower Sites and Construction Equipment [Member]
Total property, plant, and equipment	36	36
Property, Plant, and Equipment in Service [Member]
Total property, plant, and equipment	41,413	32,034
Construction in Progress [Member]
Total property, plant, and equipment	$ 878	$ 346