Note J - Segment Information - Schedule of Revenue Percentage By Product (Details) - Product Concentration Risk [Member] - Revenue Benchmark [Member]	3 Months Ended		9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
USANA Nutritionals [Member]
Percentage of product revenue	85.00%	81.00%	83.00%	83.00%
USANA Foods [Member]
Percentage of product revenue	9.00%	9.00%	11.00%	8.00%
Personal Care and Skincare [Member]
Percentage of product revenue	5.00%	9.00%	5.00%	8.00%
All Other [Member]
Percentage of product revenue	1.00%	1.00%	1.00%	1.00%