Note 14 - Activity of Business Segments - Consolidated Net Sales (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Net sales	$ 44,025,000	$ 46,176,000
Building Supply [Member] | Operating Segments [Member]
Net sales	24,641,000	27,343,000
Disposable Protective Apparel [Member] | Operating Segments [Member]
Net sales	14,250,000	14,219,000
Infection Control [Member] | Operating Segments [Member]
Net sales	$ 5,134,000	$ 4,614,000