Note 4 - Revenue Recognition - Disaggregation of Net Sales by Product Line (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 28, 2025	Jun. 29, 2024	Jun. 28, 2025	Jun. 29, 2024
Revenue	$ 179,886	$ 145,775	$ 470,262	$ 394,894
Welded Wire Reinforcement [Member]
Revenue	117,691	84,486	300,165	223,038
Prestressed Concrete Strand [Member]
Revenue	$ 62,195	$ 61,289	$ 170,097	$ 171,856

Amount, excluding 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.

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+ Details