Note 10 - Major Customers and Export Sales (Details Textual)	3 Months Ended		6 Months Ended
	Mar. 27, 2021	Mar. 28, 2020	Mar. 27, 2021	Mar. 28, 2020
Number of Countries in Which Products are Sold	2		4	2
Customer Concentration Risk [Member] | Revenue Benchmark [Member]
Number of Major Customers	4	2	4	2
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Four Customers [Member]
Concentration Risk, Percentage	84.00%		75.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Customer One [Member]
Concentration Risk, Percentage	40.00%	63.00%	31.00%	63.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Customer Two [Member]
Concentration Risk, Percentage	16.00%	24.00%	19.00%	12.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Customer Three [Member]
Concentration Risk, Percentage	16.00%		13.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Customer Four [Member]
Concentration Risk, Percentage	12.00%		12.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Two Customers [Member]
Concentration Risk, Percentage		87.00%		75.00%