Note 10 - Activity of Business Segments - Consolidated Net Property and Equipment, Goodwill and Intangible Assets (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Consolidated assets	$ 3,341,000	$ 3,315,000
Operating Segments [Member]
Consolidated assets	2,319,000	2,308,000
Operating Segments [Member] | Building Supply [Member]
Consolidated assets	1,929,000	1,908,000
Operating Segments [Member] | Disposable Protective Apparel [Member]
Consolidated assets	390,000	400,000
Corporate, Non-Segment [Member]
Consolidated assets	$ 1,022,000	$ 1,007,000