Note 6 - Segment Information - Reportable Segments (Details) - USD ($)		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Net sales		$ 4,596,411	$ 4,634,177	$ 8,125,102	$ 8,705,655
Cost of goods sold		3,167,982	2,971,862	5,687,554	5,680,921
Gross profit		1,428,429	1,662,315	2,437,548	3,024,734
Selling general and administrative*	[1]	1,338,861	1,308,963	2,720,826	2,657,946
Research and development*	[1]	270,465	156,472	449,307	310,548
Income (loss) from operations		(180,897)	196,880	(732,585)	56,240
Trade receivables		2,223,445		2,223,445		$ 2,215,215
Segment Reconciling Items [Member]
Net sales
Cost of goods sold
Gross profit
Selling general and administrative*	[1]	500,597	492,864	992,353	1,011,858
Research and development*	[1]	270,465	156,472	449,307	310,548
Income (loss) from operations		(771,062)	(649,336)	(1,441,660)	(1,322,406)
Trade receivables		5,919		5,919		(43,147)
Chromaline [Member] | Operating Segments [Member]
Net sales		3,107,116	3,099,892	5,136,457	5,440,702
Cost of goods sold		2,280,224	2,037,949	3,833,834	3,702,827
Gross profit		826,892	1,061,943	1,302,623	1,737,875
Selling general and administrative*	[1]	467,091	441,393	912,094	866,722
Research and development*	[1]
Income (loss) from operations		359,801	620,550	390,529	871,153
Trade receivables		1,568,512		1,568,512		1,550,411
Ikonics Imaging [Member] | Operating Segments [Member]
Net sales		958,128	968,933	2,046,934	2,188,281
Cost of goods sold		501,006	509,613	1,086,510	1,133,224
Gross profit		457,122	459,320	960,424	1,055,057
Selling general and administrative*	[1]	248,050	244,633	570,503	529,658
Research and development*	[1]
Income (loss) from operations		209,072	214,687	389,921	525,399
Trade receivables		323,741		323,741		360,551
DTX [Member] | Operating Segments [Member]
Net sales		112,601	94,322	205,361	182,988
Cost of goods sold		51,547	33,612	85,593	59,004
Gross profit		61,054	60,710	119,768	123,984
Selling general and administrative*	[1]	34,761	32,596	69,366	67,448
Research and development*	[1]
Income (loss) from operations		26,293	28,114	50,402	56,536
Trade receivables		26,559		26,559		15,692
AMS [Member] | Operating Segments [Member]
Net sales		418,566	471,030	736,350	893,684
Cost of goods sold		335,205	390,688	681,617	785,866
Gross profit		83,361	80,342	54,733	107,818
Selling general and administrative*	[1]	88,362	97,477	176,510	182,260
Research and development*	[1]
Income (loss) from operations		(5,001)	$ (17,135)	(121,777)	$ (74,442)
Trade receivables		$ 298,714		$ 298,714		$ 331,708

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