Condensed Consolidated Statements Of Operations (USD $) In Thousands, except Share data	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Condensed Consolidated Statements Of Operations [Abstract]
Net sales	$ 1,632	$ 1,469	$ 4,692	$ 4,519
Cost of goods sold	694	605	1,977	1,881
Gross profit	938	864	2,715	2,638
Operating expenses:
Selling and marketing	345	259	1,040	892
General and administrative	242	233	721	785
Research and development	111	142	330	360
Total operating expenses	698	634	2,091	2,037
Operating income	240	230	624	601
Non-operating income (expense):
Gain on disposal of investment securities	0	0	1	0
Interest income	1	0	5	2
Loss on disposal of fixed assets	(18)	0	(18)	0
Other income	2	2	5	6
Total non-operating income (expense)	(15)	2	(7)	8
Income from continuing operations before income taxes	225	232	617	609
Income taxes	90	92	246	249
Income before discontinued operations	135	140	371	360
Loss from discontinued operations, net of income taxes	(17)	(7)	(41)	(10)
Net income	118	133	330	350
Other comprehensive income (loss):
Change in unrealized value of available for sale securities, net of income tax	(863)	162	(301)	338
Total comprehensive income (loss)	$ (745)	$ 295	$ 29	$ 688
Net Income (Loss) per Share Data:
Net income per share continuing operations	$ 0.04	$ 0.04	$ 0.11	$ 0.10
Net loss per share discontinued operations	$ (0.01)	$ 0.00	$ (0.01)	$ 0.00
Net income per share	$ 0.03	$ 0.04	$ 0.10	$ 0.10
Weighted average shares	3,389,506	3,381,888	3,387,192	3,381,837
Diluted
Net income per share continuing operations	$ 0.04	$ 0.04	$ 0.11	$ 0.10
Net loss per share discontinued operations	$ (0.01)	$ 0.00	$ (0.01)	$ 0.00
Net income per share	$ 0.03	$ 0.04	$ 0.10	$ 0.10
Weighted average shares	3,406,486	3,405,484	3,405,738	3,405,433
Dividends paid per share	$ 0.04	$ 0.04	$ 0.12	$ 0.12