Condensed Consolidated Statements Of Operations (USD $) In Thousands, except Share data	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Condensed Consolidated Statements Of Operations
Net sales	$ 1,667	$ 1,700	$ 3,254	$ 3,257
Cost of goods sold	680	678	1,317	1,298
Gross profit	987	1,022	1,937	1,959
Operating expenses:
Selling and marketing	384	344	763	698
General and administrative	242	278	513	588
Research and development	168	161	317	307
Total operating expenses	794	783	1,593	1,593
Operating income	193	239	344	366
Non-operating income:
Interest income	1	2	4	2
Gain on investment securities	1	0	1	0
Other income	1	2	3	4
Total non-operating income	3	4	8	6
Income before income taxes	196	243	352	372
Income taxes	78	97	140	155
Net income	118	146	212	217
Other comprehensive income (loss):
Change in unrealized value of investments, net of income tax	(80)	(224)	561	176
Total comprehensive income (loss)	$ 38	$ (78)	$ 773	$ 393
Net Income per Share Data:
Net income per share	$ 0.03	$ 0.04	$ 0.06	$ 0.06
Weighted average shares	3,388,241	3,380,290	3,386,016	3,380,213
Diluted
Net income per share	$ 0.03	$ 0.04	$ 0.06	$ 0.06
Weighted average shares	3,405,468	3,405,070	3,405,358	3,404,993
Dividends paid per share	$ 0.04	$ 0.04	$ 0.08	$ 0.08