CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED) (USD $) In Thousands, except Per Share data	3 Months Ended		6 Months Ended
	Jul. 02, 2011	Jul. 03, 2010	Jul. 02, 2011	Jul. 03, 2010
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED) [Abstract]
Net sales	$ 47,768	$ 41,748	$ 87,550	$ 76,121
Cost of goods sold	20,382	17,843	37,009	32,697
Gross Profit	27,386	23,905	50,541	43,424
Selling, general and administrative expenses	19,721	17,435	38,673	34,135
Service and distribution costs	2,116	1,841	3,695	3,469
Research and development expenses	707	708	1,278	1,373
Operating Income	4,842	3,921	6,895	4,447
Interest income	3	2	6	4
Interest expense	(160)	(305)	(387)	(593)
Other income	(6)	164	28	173
Interest and Other Expense	(163)	(139)	(353)	(416)
Income Before Income Taxes	4,679	3,782	6,542	4,031
Income tax provision	1,527	1,068	2,132	1,143
Net Income	$ 3,152	$ 2,714	$ 4,410	$ 2,888
Net Income Per Share:
Basic (in dollars per share)	$ 0.26	$ 0.20	$ 0.36	$ 0.22
Diluted (in dollars per share)	$ 0.24	$ 0.20	$ 0.34	$ 0.21
Weighted Average Shares Outstanding:
Denominator for Basic Net Income Per Share (in shares)	12,191	13,339	12,153	13,332
Effect of dilutive securities (in shares)	810	119	790	102
Denominator for Diluted Net Income Per Share (in shares)	13,001	13,458	12,943	13,434