Note 12 - Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2026	Jun. 30, 2025
Net Sales	$ 239,971	$ 134,777
Flat-roll [Member]
Net Sales	221,753	124,067
Flat-roll [Member] \| Prime Coil [Member]
Net Sales	220,589	122,846
Flat-roll [Member] \| Customer Owned [Member]
Net Sales	1,164	1,221
Tubular [Member]
Net Sales	18,218	10,710
Tubular [Member] \| Manufactured Pipe [Member]
Net Sales	$ 18,218	$ 10,710

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details