Condensed Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
REVENUES:
Net sales	$ 78,555	$ 78,537	$ 151,668	$ 152,710
Other	122	124	239	250
TOTAL REVENUE	78,677	78,661	151,907	152,960
COST OF GOODS SOLD	41,135	40,623	78,338	78,128
Gross profit	37,542	38,038	73,569	74,832
OPERATING EXPENSES:
Selling, general and administrative	24,278	23,182	46,797	46,048
Research and development	4,566	3,906	8,197	5,809
Total operating expenses	28,844	27,088	54,994	51,857
Income from operations	8,698	10,950	18,575	22,975
OTHER INCOME(EXPENSE)	207	212	417	380
Income before income taxes	8,905	11,162	18,992	23,355
PROVISION FOR INCOME TAXES	(3,027)	(3,795)	(6,457)	(7,303)
NET INCOME	$ 5,878	$ 7,367	$ 12,535	$ 16,052
NET INCOME PER SHARE
Basic (in dollars per share)	$ 0.39	$ 0.50	$ 0.83	$ 1.10
Diluted (in dollars per share)	$ 0.38	$ 0.48	$ 0.81	$ 1.06
WEIGHTED AVERAGE NUMBER OF SHARES
Basic (in shares)	15,242	14,617	15,170	14,562
Diluted (in shares)	15,362	15,216	15,439	15,147