For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Note 1 - Basis of Presentation (Details Textual) - Sell-through Distributors Concentration Risk [Member]	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019	Dec. 28, 2019
Revenue Benchmark [Member]
Concentration Risk, Percentage	82.00%	81.00%	81.00%	82.00%
Accounts Receivable [Member] \| Large Distributor One [Member]
Concentration Risk, Percentage			53.00%		40.00%
Accounts Receivable [Member] \| Large Distributor Two [Member]
Concentration Risk, Percentage			31.00%		38.00%