Business Segments - Summary of company's operations (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Segment Reporting Information [Line Items]
Revenues from unaffiliated customers	$ 7,516	$ 8,550	$ 23,302	$ 24,592
Cost of goods sold, exclusive of depreciation and amortization	(5,536)	(5,821)	(17,081)	(17,046)
Selling, general and administrative	(1,275)	(1,145)	(3,753)	(3,543)
Interest expense	(11)	(12)	(34)	(37)
Depreciation and amortization	(141)	(139)	(437)	(427)
Other income, net	2	150	12	164
Income (loss) from continuing operations before income tax provision	555	1,583	2,009	3,703
Income tax provision (benefit)	249	476	663	1,115
Income (loss) from continuing operations	306	1,107	1,346	2,588
Discontinued Operations:
Loss from operations of a discontinued component, net of income tax benefit	(188)	(203)	(591)	(550)
Loss on disposal of QCC and AMP, net of income tax benefit	(262)		(530)
Loss from discontinued operation	(450)	(203)	(1,121)	(550)
Net income	(144)	904	225	2,038
Capital expenditures	258	250	394	435
Advanced Technology Group
Segment Reporting Information [Line Items]
Revenues from unaffiliated customers	5,783	5,409	16,671	15,817
Cost of goods sold, exclusive of depreciation and amortization	(4,080)	(3,522)	(11,445)	(10,571)
Selling, general and administrative	(842)	(704)	(2,411)	(2,201)
Interest expense	(11)	(12)	(34)	(37)
Depreciation and amortization	(104)	(105)	(323)	(319)
Other income, net		145	5	153
Income (loss) from continuing operations before income tax provision	746	1,211	2,463	2,842
Income tax provision (benefit)	335	365	812	855
Income (loss) from continuing operations	411	846	1,651	1,987
Discontinued Operations:
Loss from operations of a discontinued component, net of income tax benefit
Loss on disposal of QCC and AMP, net of income tax benefit
Loss from discontinued operation
Net income	411	846	1,651	1,987
Capital expenditures	234	70	327	151
Consumer Products Group
Segment Reporting Information [Line Items]
Revenues from unaffiliated customers	1,733	3,141	6,631	8,775
Cost of goods sold, exclusive of depreciation and amortization	(1,456)	(2,299)	(5,636)	(6,475)
Selling, general and administrative	(433)	(441)	(1,342)	(1,342)
Interest expense
Depreciation and amortization	(37)	(34)	(114)	(108)
Other income, net	2	5	7	11
Income (loss) from continuing operations before income tax provision	(191)	372	(454)	861
Income tax provision (benefit)	(86)	111	(149)	260
Income (loss) from continuing operations	(105)	261	(305)	601
Discontinued Operations:
Loss from operations of a discontinued component, net of income tax benefit	(188)	(203)	(591)	(550)
Loss on disposal of QCC and AMP, net of income tax benefit	(262)		(530)
Loss from discontinued operation	(450)	(203)	(1,121)	(550)
Net income	(555)	58	(1,426)	51
Capital expenditures	$ 24	$ 180	$ 67	$ 284