Note 5 - Segment Information - Reportable Segments (Details) - USD ($)		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019
Net sales		$ 13,432,220	$ 17,618,559
Cost of goods sold		9,527,143	12,221,370
Gross profit (loss)		3,905,077	5,397,189
Selling, general, and administrative*	[1]	5,019,604	5,483,586
Research and development*	[1]	671,493	870,279
Income (loss) from operations		(1,786,020)	(956,676)
Trade receivables		2,119,213	2,434,718
Segment Reconciling Items [Member]
Net sales
Cost of goods sold
Gross profit (loss)
Selling, general, and administrative*	[1]	2,441,256	2,058,000
Research and development*	[1]	671,493	870,279
Income (loss) from operations		(3,112,749)	(2,928,279)
Trade receivables		(47,154)	(52,421)
Chromaline [Member] | Operating Segments [Member]
Net sales		8,475,743	11,472,111
Cost of goods sold		6,222,902	8,389,404
Gross profit (loss)		2,252,841	3,082,707
Selling, general, and administrative*	[1]	1,297,045	1,832,473
Research and development*	[1]
Income (loss) from operations		955,796	1,250,234
Trade receivables		1,676,592	1,916,066
Ikonics Imaging [Member] | Operating Segments [Member]
Net sales		3,709,318	4,191,175
Cost of goods sold		1,972,076	2,273,641
Gross profit (loss)		1,737,242	1,917,534
Selling, general, and administrative*	[1]	880,404	1,081,847
Research and development*	[1]
Income (loss) from operations		856,838	835,687
Trade receivables		396,116	304,791
DTX [Member] | Operating Segments [Member]
Net sales		294,929	393,804
Cost of goods sold		140,866	157,650
Gross profit (loss)		154,063	236,154
Selling, general, and administrative*	[1]	125,752	149,924
Research and development*	[1]
Income (loss) from operations		28,311	86,230
Trade receivables		35,983	13,919
AMS [Member] | Operating Segments [Member]
Net sales		952,230	1,561,469
Cost of goods sold		1,191,299	1,400,675
Gross profit (loss)		(239,069)	160,794
Selling, general, and administrative*	[1]	275,147	361,342
Research and development*	[1]
Income (loss) from operations		(514,216)	(200,548)
Trade receivables		$ 57,676	$ 252,363

[1] The Company does not allocate all general and administrative expenses or any research and development expenses to its operating segments for internal reporting.