Note 4 - Inventories - Schedule of Inventory (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Mar. 31, 2025
Total	$ 161,566	$ 113,689
Flat-Roll Inventory [Member]
Flat-Roll raw material	110,125	85,865
Flat-Roll finished goods	30,614	15,737
Tubular Inventory [Member]
Flat-Roll raw material	11,164	7,055
Flat-Roll finished goods	$ 9,663	$ 5,032

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
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-Section S99
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