Note 4 - Revenue Recognition - Disaggregation of Net Sales by Product Line (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Apr. 02, 2022	Apr. 03, 2021	Apr. 02, 2022	Apr. 03, 2021
Revenue	$ 213,209	$ 138,999	$ 391,668	$ 258,604
UNITED STATES
Revenue	211,527	136,778	388,268	255,115
Non-US [Member]
Revenue	1,682	2,221	3,400	3,489
Welded Wire Reinforcement [Member]
Revenue	133,651	81,923	247,044	155,949
Prestressed Concrete Strand [Member]
Revenue	$ 79,558	$ 57,076	$ 144,624	$ 102,655

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