Consolidated Statements Of Operations And Comprehensive Income (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Consolidated Statements Of Operations And Comprehensive Income [Abstract]
Net Sales	$ 6,498,000	$ 6,115,000
Cost of Goods Sold	2,858,000	2,613,000
Gross Profit	3,640,000	3,502,000
Operating Expenses:
Selling and marketing	1,344,000	1,369,000
General and administrative	1,022,000	956,000
Research and development	443,000	437,000
Total Operating Expenses	2,809,000	2,762,000
Operating Income	831,000	740,000
Non-operating Income (Expense):
Gain on sale of investment securities	794,000	73,000
Interest income	4,000	6,000
Loss on disposal of fixed assets	0	(18,000)
Other income	13,000	8,000
Total Non-operating Income	811,000	69,000
Income from Continuing Operations Before Income Taxes	1,642,000	809,000
Income Taxes	556,000	211,000
Income before Discontinued Operations	1,086,000	598,000
Loss from Discontinued Operations, Net of Income Taxes	0	(50,000)
Net Income	1,086,000	548,000
Other Comprehensive Income:
Change in Unrealized Value of Investments, Net of Tax	313,000	218,000
Total Comprehensive Income	$ 1,399,000	$ 766,000
Basic
Net income per share continuing operations	$ 0.32	$ 0.17
Net loss per share discontinued operations	$ 0.00	$ (0.01)
Net income per share	$ 0.32	$ 0.16
Weighted average shares	3,391,332	3,387,192
Diluted
Net income per share continuing operations	$ 0.31	$ 0.17
Net loss per share discontinued operations	$ 0.00	$ (0.01)
Net income per share	$ 0.31	$ 0.16
Weighted average shares	3,412,288	3,405,738
Dividends paid per common share	$ 0.16	$ 0.16