CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
NET SALES	$ 129,577us-gaap_SalesRevenueGoodsNet	$ 119,236us-gaap_SalesRevenueGoodsNet
COST OF SALES	74,194us-gaap_CostOfGoodsSold	67,193us-gaap_CostOfGoodsSold
GROSS PROFIT	55,383us-gaap_GrossProfit	52,043us-gaap_GrossProfit
OPERATING EXPENSES:
Selling, general, and administrative	36,885	36,763
Research and development	9,672us-gaap_ResearchAndDevelopmentExpense	8,780us-gaap_ResearchAndDevelopmentExpense
Contingent consideration expense	122	11
Total operating expenses	46,679us-gaap_OperatingExpenses	45,554us-gaap_OperatingExpenses
INCOME FROM OPERATIONS	8,704us-gaap_OperatingIncomeLoss	6,489us-gaap_OperatingIncomeLoss
OTHER INCOME (EXPENSE):
Interest income	53us-gaap_InvestmentIncomeInterest	67us-gaap_InvestmentIncomeInterest
Interest expense	(1,574)us-gaap_InterestExpense	(2,606)us-gaap_InterestExpense
Other income (expense) — net	280us-gaap_OtherNonoperatingIncomeExpense	(64)us-gaap_OtherNonoperatingIncomeExpense
Other (expense) — net	(1,241)us-gaap_NonoperatingIncomeExpense	(2,603)us-gaap_NonoperatingIncomeExpense
INCOME BEFORE INCOME TAXES	7,463	3,886
INCOME TAX EXPENSE	2,289us-gaap_IncomeTaxExpenseBenefit	1,063us-gaap_IncomeTaxExpenseBenefit
NET INCOME	$ 5,174us-gaap_ProfitLoss	$ 2,823us-gaap_ProfitLoss
EARNINGS PER COMMON SHARE:
Basic (in dollars per share)	$ 0.12us-gaap_EarningsPerShareBasic	$ 0.07us-gaap_EarningsPerShareBasic
Diluted (in dollars per share)	$ 0.12us-gaap_EarningsPerShareDiluted	$ 0.07us-gaap_EarningsPerShareDiluted
AVERAGE COMMON SHARES:
Basic (in shares)	43,703	42,865
Diluted (in shares)	44,145	43,234

Business Combination, Contingent Consideration Arrangements, Contingent Consideration Benefit

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