Note 4 - Inventories - Schedule of Inventory (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Mar. 31, 2026
Total	$ 191,080	$ 172,223
Flat-Roll Inventory [Member]
Flat-Roll raw material	131,118	120,763
Flat-Roll finished goods	32,329	31,068
Tubular Inventory [Member]
Flat-Roll raw material	17,063	9,441
Flat-Roll finished goods	$ 10,570	$ 10,951