Note 5 - Segment Information - Reportable Segments (Details) - USD ($)		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018
Net sales		$ 17,618,559	$ 18,213,653
Cost of goods sold		12,221,370	11,959,626
Gross profit		5,397,189	6,254,027
Selling, general, and administrative*	[1]	5,483,586	5,350,966
Research and development*	[1]	870,279	677,242
Income (loss) from operations		(956,676)	225,819
Trade receivables		2,434,718	2,215,215
Segment Reconciling Items [Member]
Net sales
Cost of goods sold
Gross profit
Selling, general, and administrative*	[1]	2,058,000	2,032,116
Research and development*	[1]	870,279	677,242
Income (loss) from operations		(2,928,279)	(2,709,358)
Trade receivables		(52,421)	(43,147)
Chromaline [Member] | Operating Segments [Member]
Net sales		11,472,111	11,610,414
Cost of goods sold		8,389,404	7,949,894
Gross profit		3,082,707	3,660,520
Selling, general, and administrative*	[1]	1,832,473	1,777,197
Research and development*	[1]
Income (loss) from operations		1,250,234	1,883,323
Trade receivables		1,916,066	1,550,411
Ikonics Imaging [Member] | Operating Segments [Member]
Net sales		4,191,175	4,397,826
Cost of goods sold		2,273,641	2,323,425
Gross profit		1,917,534	2,074,401
Selling, general, and administrative*	[1]	1,081,847	1,023,422
Research and development*	[1]
Income (loss) from operations		835,687	1,050,979
Trade receivables		304,791	360,551
DTX [Member] | Operating Segments [Member]
Net sales		393,804	420,714
Cost of goods sold		157,650	137,039
Gross profit		236,154	283,675
Selling, general, and administrative*	[1]	149,924	150,698
Research and development*	[1]
Income (loss) from operations		86,230	132,977
Trade receivables		13,919	15,692
AMS [Member] | Operating Segments [Member]
Net sales		1,561,469	1,784,699
Cost of goods sold		1,400,675	1,549,268
Gross profit		160,794	235,431
Selling, general, and administrative*	[1]	361,342	367,533
Research and development*	[1]
Income (loss) from operations		(200,548)	(132,102)
Trade receivables		$ 252,363	$ 331,708

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