Note 9 - Activity of Business Segments - Consolidated Net Sales (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 30, 2022	Mar. 31, 2021	Mar. 30, 2021
Net sales	$ 17,661,000	$ 17,661,000	$ 23,161,000	$ 23,161,000
Building Supply [Member] | Operating Segments [Member]
Net sales	10,237,000		8,340,000
Disposable Protective Apparel [Member] | Operating Segments [Member]
Net sales	$ 7,424,000		$ 14,821,000