Note 3 - Inventories - Schedule of Inventory (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Mar. 31, 2025
Total	$ 103,458	$ 113,689
Flat-Roll Inventory [Member]
Flat-Roll raw material	71,441	85,865
Flat-Roll finished goods	16,439	15,737
Tubular Inventory [Member]
Flat-Roll raw material	9,619	7,055
Flat-Roll finished goods	$ 5,959	$ 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
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