Note 10 - Activity of Business Segments - Consolidated Net Property and Equipment, Goodwill and Intangible Assets (Details) - USD ($)	Mar. 31, 2018	Dec. 31, 2017
Consolidated assets	$ 3,190,000	$ 3,234,000
Operating Segments [Member]
Consolidated assets	2,387,000	2,447,000
Operating Segments [Member] | Building Supply [Member]
Consolidated assets	2,050,000	2,098,000
Operating Segments [Member] | Disposable Protective Apparel [Member]
Consolidated assets	325,000	336,000
Operating Segments [Member] | Infection Control [Member]
Consolidated assets	12,000	13,000
Corporate, Non-Segment [Member]
Consolidated assets	$ 803,000	$ 787,000