Condensed Consolidated Statements Of Operations And Comprehensive Income (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Consolidated Statements Of Operations And Comprehensive Income [Abstract]
Net sales	$ 1,708	$ 1,567	$ 4,813	$ 5,004
Cost of goods sold	727	696	2,042	2,189
Gross profit	981	871	2,771	2,815
Operating expenses:
Selling and marketing	378	305	1,163	1,098
General and administrative	444	244	1,026	769
Research and development	144	105	374	333
Total operating expenses	966	654	2,563	2,200
Operating income	15	217	208	615
Non-operating income:
Gain on sale of available-for-sale securities	129	0	530	0
Interest income	3	1	5	5
Other income	3	3	11	9
Total non-operating income	135	4	546	14
Income before income taxes	150	221	754	629
Income taxes	46	77	214	224
Net income	104	144	540	405
Other comprehensive income (loss):
Change in unrealized value of available-for-sale securities, net of income tax	41	378	(310)	263
Reclassification of gains included in net income, net of income tax	(80)	0	(329)	0
Net change in other comprehensive income (loss)	(39)	378	(639)	263
Total comprehensive income (loss)	$ 65	$ 522	$ (99)	$ 668
Basic
Net income per share	$ 0.03	$ 0.04	$ 0.15	$ 0.11
Weighted average shares	3,394,696	3,391,900	3,394,033	3,391,126
Diluted
Net income per share	$ 0.02	$ 0.04	$ 0.15	$ 0.11
Weighted average shares	3,511,784	3,417,032	3,448,064	3,410,843
Dividends paid per common share	$ 0.00	$ 0.04	$ 0.08	$ 0.12