Note 3 - Revenue Recognition - Disaggregation of Net Sales by Product Line (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 30, 2024	Apr. 01, 2023	Mar. 30, 2024	Apr. 01, 2023
Revenue	$ 127,394	$ 159,051	$ 249,119	$ 325,950
Welded Wire Reinforcement [Member]
Revenue	69,750	91,378	138,552	187,346
Prestressed Concrete Strand [Member]
Revenue	$ 57,644	$ 67,673	$ 110,567	$ 138,604

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