Note 14 - Activity of Business Segments - Reconciliation of Total Segment Income to Total Consolidated Net Income (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Consolidated net income	$ 2,633,000	$ 3,168,000
Provision for income taxes	1,037,000	1,007,000
Operating Segments [Member]
Consolidated net income	8,503,000	8,597,000
Operating Segments [Member] | Building Supply [Member]
Consolidated net income	4,143,000	5,345,000
Operating Segments [Member] | Disposable Protective Apparel [Member]
Consolidated net income	2,516,000	1,671,000
Operating Segments [Member] | Infection Control [Member]
Consolidated net income	1,844,000	1,581,000
Corporate, Non-Segment [Member]
Consolidated net income	$ 4,833,000	$ 4,422,000