Note 4 - Revenue Recognition - Disaggregation of Net Sales by Product Line (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 29, 2025	Mar. 30, 2024	Mar. 29, 2025	Mar. 30, 2024
Revenue	$ 160,656	$ 127,394	$ 290,376	$ 249,119
Welded Wire Reinforcement [Member]
Revenue	100,019	69,750	182,473	138,552
Prestressed Concrete Strand [Member]
Revenue	$ 60,637	$ 57,644	$ 107,903	$ 110,567

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