Note 4 - Revenue Recognition - Disaggregation of Net Sales by Product Line (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jul. 03, 2021	Jun. 27, 2020	Jul. 03, 2021	Jun. 27, 2020
Revenue	$ 160,739	$ 121,959	$ 419,343	$ 334,387
UNITED STATES
Revenue	158,710	120,985	413,826	332,791
Non-US [Member]
Revenue	2,029	974	5,517	1,596
Welded Wire Reinforcement [Member]
Revenue	96,422	75,103	252,371	206,284
Prestressed Concrete Strand [Member]
Revenue	$ 64,317	$ 46,856	$ 166,972	$ 128,103

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