Note 13 - Segment Reporting - Segment Information (Details) - USD ($)		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017
Assets		$ 52,514,562	$ 58,978,250
Revenue		24,334,331	41,128,639
Operating (loss)/income		(5,254,519)	7,218,873
Pretax (loss)/income		(5,557,583)	7,195,355
Corporate, Non-Segment [Member]
Assets			1,609,000
Revenue
Operating (loss)/income		(3,164,000)	(2,615,000)
Pretax (loss)/income		(3,164,000)	(2,615,000)
Intersegment Eliminations [Member]
Assets	[1]	(9,000)	(1,000)
Revenue	[1]	(1,022,000)	(1,996,000)
Operating (loss)/income	[1]
Pretax (loss)/income	[1]
CVD [Member] | Operating Segments [Member]
Assets		40,467,000	42,152,000
Revenue		17,860,000	34,965,000
Operating (loss)/income		(1,754,000)	9,232,000
Pretax (loss)/income		(1,691,000)	9,243,000
SDC [Member] | Operating Segments [Member]
Assets		4,870,000	5,850,000
Revenue		5,503,000	7,427,000
Operating (loss)/income		958,000	2,008,000
Pretax (loss)/income		987,000	2,011,000
Materials [Member] | Operating Segments [Member]
Assets		7,187,000	9,368,000
Revenue		1,993,000	733,000
Operating (loss)/income		(1,295,000)	(1,406,000)
Pretax (loss)/income		$ (1,690,000)	$ (1,444,000)

[1] All elimination entries represent intersegment transactions eliminated in consolidation for external financial reporting.