Business Segments - Summary of company's operations (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Business Segments
Revenues from unaffiliated customers	$ 10,802	$ 11,168
Cost of goods sold, inclusive of dep. and amort.	(9,887)	(8,211)
Gross profit (loss)	915	2,957
Operating expenses:
Selling, general and administrative	(2,826)	(2,501)
Operating (loss)/income	(1,911)	456
Other (expense)/income:
Interest expense	(53)	(70)
Gain on sale of equipment		26
Total other expense, net	(53)	(44)
(Loss)/income before income tax provision	(1,964)	412
Income tax benefit/(provision)	417	(87)
Net (loss)/income	(1,547)	325
Total Assets	45,849		$ 45,294
Operating Segments
Business Segments
Revenues from unaffiliated customers	10,802	11,168
Cost of goods sold, inclusive of dep. and amort.	(9,887)	(8,211)
Gross profit (loss)	$ 915	$ 2,957
Gross margin %	8.50%	26.50%
Operating expenses:
Selling, general and administrative	$ (2,826)	$ (2,501)
Total operating costs and expenses	(12,713)	(10,712)
Operating (loss)/income	1,911	(456)
Other (expense)/income:
Interest expense	(53)	(70)
Gain on sale of equipment		26
Total other expense, net	(53)	(44)
(Loss)/income before income tax provision	(1,964)	412
Income tax benefit/(provision)	417	(87)
Net (loss)/income	(1,547)	325
Total Assets	45,849	51,928
Capital expenditures	437	77
Foreign derived sales	2,086	2,999
Operating Segments | ATG
Business Segments
Revenues from unaffiliated customers	9,060	9,168
Cost of goods sold, inclusive of dep. and amort.	(8,076)	(6,496)
Gross profit (loss)	$ 984	$ 2,672
Gross margin %	10.90%	29.10%
Operating expenses:
Selling, general and administrative	$ (2,175)	$ (2,093)
Total operating costs and expenses	(10,251)	(8,589)
Operating (loss)/income	1,191	(579)
Other (expense)/income:
Interest expense	(53)	(70)
Gain on sale of equipment		26
Total other expense, net	(53)	(44)
(Loss)/income before income tax provision	(1,244)	535
Income tax benefit/(provision)	264	(113)
Net (loss)/income	(980)	422
Total Assets	36,096	42,382
Capital expenditures	302	77
Foreign derived sales	2,023	2,962
Operating Segments | CPG
Business Segments
Revenues from unaffiliated customers	1,742	2,000
Cost of goods sold, inclusive of dep. and amort.	(1,811)	(1,715)
Gross profit (loss)	$ (69)	$ 285
Gross margin %	(4.00%)	14.30%
Operating expenses:
Selling, general and administrative	$ (651)	$ (408)
Total operating costs and expenses	(2,462)	(2,123)
Operating (loss)/income	720	123
Other (expense)/income:
(Loss)/income before income tax provision	(720)	(123)
Income tax benefit/(provision)	153	26
Net (loss)/income	(567)	(97)
Total Assets	9,753	9,546
Capital expenditures	135
Foreign derived sales	$ 63	$ 37