Note 10 - Activity of Business Segments - Consolidated Net Property and Equipment, Goodwill and Intangible Assets (Details) - USD ($)	Jun. 30, 2020	Dec. 31, 2019
Consolidated assets	$ 4,068,000	$ 4,009,000
Operating Segments [Member]
Consolidated assets	3,021,000	2,954,000
Operating Segments [Member] | Building Supply [Member]
Consolidated assets	1,909,000	1,867,000
Operating Segments [Member] | Disposable Protective Apparel [Member]
Consolidated assets	1,112,000	1,087,000
Corporate, Non-Segment [Member]
Consolidated assets	$ 1,047,000	$ 1,055,000