CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Income Statement [Abstract]
NET SALES	$ 128,808	$ 115,210	$ 376,909	$ 329,033
COST OF SALES	71,387	64,180	211,821	188,025
GROSS PROFIT	57,421	51,030	165,088	141,008
OPERATING EXPENSES:
Selling, general, and administrative	36,328	31,350	111,682	95,002
Research and development	8,688	7,308	27,109	25,064
Intangible assets impairment charge	1,102	8,089	1,102	8,089
Contingent consideration benefit	(773)	(4,108)	(754)	(4,075)
Total operating expenses	45,345	42,639	139,139	124,080
INCOME FROM OPERATIONS	12,076	8,391	25,949	16,928
OTHER INCOME (EXPENSE):
Interest income	41	69	187	200
Interest (expense)	(2,008)	(1,916)	(6,967)	(5,297)
Other income (expense) — net	144	(104)	52	(174)
Other (expense) — net	(1,823)	(1,951)	(6,728)	(5,271)
INCOME BEFORE INCOME TAXES	10,253	6,440	19,221	11,657
INCOME TAX EXPENSE	2,489	833	4,918	1,627
NET INCOME	$ 7,764	$ 5,607	$ 14,303	$ 10,030
EARNINGS PER COMMON SHARE:
Basic (in dollars per share)	$ 0.18	$ 0.13	$ 0.33	$ 0.24
Diluted (in dollars per share)	$ 0.18	$ 0.13	$ 0.33	$ 0.23
AVERAGE COMMON SHARES:
Basic (in shares)	43,229	42,596	43,053	42,560
Diluted (in shares)	43,398	42,872	43,315	42,793