Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Statement [Abstract]
REVENUES	$ 8,071	$ 8,588	$ 23,748	$ 23,058
Type of Revenue [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Costs and expenses:
Manufacturing cost of sales	$ 5,203	$ 5,049	$ 15,681	$ 13,970
Engineering, selling and administrative	2,159	2,417	6,514	6,676
OPERATING INCOME	709	1,122	1,553	2,412
Other income (expense):
Interest (expense) income, net	(3)		(7)	1
Loss on equity investment in unconsolidated subsidiary	(61)		(200)
Other income (expense), net	155	82	3	352
Total other income (expense), net	91	82	(204)	353
INCOME BEFORE INCOME TAXES	800	1,204	1,349	2,765
Income tax expense (benefit)	171	(3,326)	282	(3,286)
NET INCOME	$ 629	$ 4,530	$ 1,067	$ 6,051
Basic per share information:
Weighted average shares outstanding	5,212,652	4,901,698	5,159,452	4,872,461
Net income	$ 0.12	$ 0.92	$ 0.21	$ 1.24
Diluted per share information:
Weighted average shares outstanding	5,251,078	4,965,808	5,195,754	4,965,989
Net income	$ 0.12	$ 0.91	$ 0.21	$ 1.22