Note 15 - Activity of Business Segments - Reconciliation of Total Segment Income to Total Consolidated Net Income (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Consolidated net income	$ 27,086,000	$ 3,000,000
Provision for income taxes	5,162,000	680,000
Operating Segments [Member]
Consolidated net income	38,897,000	7,347,000
Operating Segments [Member] | Building Supply [Member]
Consolidated net income	5,396,000	3,491,000
Operating Segments [Member] | Disposable Protective Apparel [Member]
Consolidated net income	33,501,000	3,856,000
Corporate, Non-Segment [Member]
Consolidated net income	$ 6,649,000	$ 3,667,000