Note 10 - Activity of Business Segments - Consolidated Net Sales (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Net sales	$ 10,751,000	$ 11,847,000
Building Supply [Member] | Operating Segments [Member]
Net sales	5,939,000	6,754,000
Disposable Protective Apparel [Member] | Operating Segments [Member]
Net sales	3,295,000	3,825,000
Infection Control [Member] | Operating Segments [Member]
Net sales	$ 1,517,000	$ 1,268,000