Note 4 - Revenue Recognition - Disaggregation of Net Sales by Product Line (Details) - USD ($) $ in Thousands	3 Months Ended
Jan. 02, 2021	Dec. 28, 2019
Revenue	$ 119,605	$ 97,569
UNITED STATES
Revenue	118,337	97,257
Non-US [Member]
Revenue	1,268	312
Welded Wire Reinforcement [Member]
Revenue	74,026	61,827
Prestressed Concrete Strand [Member]
Revenue	$ 45,579	$ 35,742

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