Note 15 - Business Segment Information - Net Sales By Product Line (Details) - USD ($) $ in Thousands	12 Months Ended
Oct. 03, 2020	Sep. 28, 2019	Sep. 29, 2018
Revenue	$ 472,618	$ 455,713	$ 453,217
Welded Wire Reinforcement [Member]
Revenue	294,129	290,423	273,658
PC Strand [Member]
Revenue	$ 178,489	$ 165,290	$ 179,559

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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+ Details