Note 10 - Major Customers and Export Sales (Details Textual)	3 Months Ended		9 Months Ended
	Jun. 26, 2021	Jun. 27, 2020	Jun. 26, 2021	Jun. 27, 2020
Number of Countries in Which Products are Sold		1	4	2
Customer Concentration Risk [Member] | Revenue Benchmark [Member]
Number of Major Customers	1	3	2	2
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | One Customer [Member]
Concentration Risk, Percentage	96.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Three Customers [Member]
Concentration Risk, Percentage		92.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Customer One [Member]
Concentration Risk, Percentage		53.00%	54.00%	46.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Customer Two [Member]
Concentration Risk, Percentage		25.00%	12.00%	22.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Customer Three [Member]
Concentration Risk, Percentage		14.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Two Customers [Member]
Concentration Risk, Percentage			66.00%	68.00%