CONDENSED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Revenues	$ 6,432,442	$ 6,243,855
Cost of revenues	2,945,171	2,578,735
Gross profit	3,487,271	3,665,120
Operating Expenses:
General & administrative	993,711	995,441
Marketing & selling	1,126,658	1,124,825
Research & development	164,710	168,048
Total Operating Expenses	2,285,079	2,288,314
Operating income	1,202,192	1,376,806
Other income	91,413	510
Net income before provision for income taxes	1,293,605	1,377,316
Provision for income taxes	471,260	549,825
Net income and comprehensive income	$ 822,345	$ 827,491
Basic net income per share (in dollars per share)	$ 0.16	$ 0.16
Diluted net income per share (in dollars per share)	$ 0.16	$ 0.16
Dividends declared per share (in dollars per share)	$ 0.15	$ 0.15
Weighted average common shares outstanding, basic (in shares)	5,272,647	5,235,422
Weighted average common shares outstanding, diluted (in shares)	5,292,686	5,244,042