Business Segments - Summary of company's operations (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Segment Reporting Information [Line Items]
Revenues from unaffiliated customers	$ 7,342	$ 8,067
Cost of goods sold, exclusive of depreciation and amortization	(5,697)	(6,259)
Selling, general and administrative	(1,299)	(1,258)
Interest expense	(10)	(11)
Depreciation and amortization	(153)	(147)
Other income, net	1	8
Income (loss) from continuing operations before income tax provision	184	400
Income tax provision (benefit)	7	125
Income (loss) from continuing operations	177	275
Discontinued Operations:
Loss from operations of a discontinued component, net of income tax benefit		(212)
Net income (loss)	177	63
Capital expenditures	478	87
ATG
Segment Reporting Information [Line Items]
Revenues from unaffiliated customers	5,383	5,302
Cost of goods sold, exclusive of depreciation and amortization	(3,986)	(3,781)
Selling, general and administrative	(889)	(731)
Interest expense	(10)	(11)
Depreciation and amortization	(108)	(109)
Other income, net		4
Income (loss) from continuing operations before income tax provision	390	674
Income tax provision (benefit)	60	211
Income (loss) from continuing operations	330	463
Discontinued Operations:
Loss from operations of a discontinued component, net of income tax benefit
Net income (loss)	330	463
Capital expenditures	384	50
CPG
Segment Reporting Information [Line Items]
Revenues from unaffiliated customers	1,959	2,765
Cost of goods sold, exclusive of depreciation and amortization	(1,711)	(2,478)
Selling, general and administrative	(410)	(527)
Interest expense
Depreciation and amortization	(45)	(38)
Other income, net	1	4
Income (loss) from continuing operations before income tax provision	(206)	(274)
Income tax provision (benefit)	(53)	(86)
Income (loss) from continuing operations	(153)	(188)
Discontinued Operations:
Loss from operations of a discontinued component, net of income tax benefit		(212)
Net income (loss)	(153)	(400)
Capital expenditures	$ 94	$ 37