CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Statement [Abstract]
NET SALES	$ 509,689us-gaap_SalesRevenueGoodsNet	$ 449,049us-gaap_SalesRevenueGoodsNet	$ 394,288us-gaap_SalesRevenueGoodsNet
COST OF SALES	284,467us-gaap_CostOfGoodsSold	254,682us-gaap_CostOfGoodsSold	212,296us-gaap_CostOfGoodsSold
GROSS PROFIT	225,222us-gaap_GrossProfit	194,367us-gaap_GrossProfit	181,992us-gaap_GrossProfit
OPERATING EXPENSES:
Selling, general, and administrative	147,894	128,642	122,106
Research and development	36,632us-gaap_ResearchAndDevelopmentExpense	33,886us-gaap_ResearchAndDevelopmentExpense	27,795us-gaap_ResearchAndDevelopmentExpense
Intangible asset impairment charges	1,102	8,089	0
Contingent consideration benefit	(572)	(4,094)	0
Acquired in-process research and development	0	0	2,450
Total operating expenses	185,056us-gaap_OperatingExpenses	166,523us-gaap_OperatingExpenses	152,351us-gaap_OperatingExpenses
INCOME FROM OPERATIONS	40,166us-gaap_OperatingIncomeLoss	27,844us-gaap_OperatingIncomeLoss	29,641us-gaap_OperatingIncomeLoss
OTHER INCOME (EXPENSE):
Interest income	217us-gaap_InvestmentIncomeInterest	255us-gaap_InvestmentIncomeInterest	226us-gaap_InvestmentIncomeInterest
Interest expense	(8,829)us-gaap_InterestExpense	(8,044)us-gaap_InterestExpense	(604)us-gaap_InterestExpense
Other income (expense) — net	18us-gaap_OtherNonoperatingIncomeExpense	(216)us-gaap_OtherNonoperatingIncomeExpense	(1,645)us-gaap_OtherNonoperatingIncomeExpense
Other expense — net	(8,594)us-gaap_NonoperatingIncomeExpense	(8,005)us-gaap_NonoperatingIncomeExpense	(2,023)us-gaap_NonoperatingIncomeExpense
INCOME BEFORE INCOME TAXES	31,572	19,839	27,618
INCOME TAX EXPENSE	8,598us-gaap_IncomeTaxExpenseBenefit	3,269us-gaap_IncomeTaxExpenseBenefit	7,908us-gaap_IncomeTaxExpenseBenefit
NET INCOME	$ 22,974us-gaap_ProfitLoss	$ 16,570us-gaap_ProfitLoss	$ 19,710us-gaap_ProfitLoss
EARNINGS PER COMMON SHARE:
Basic (in dollars per share)	$ 0.53us-gaap_EarningsPerShareBasic	$ 0.39us-gaap_EarningsPerShareBasic	$ 0.47us-gaap_EarningsPerShareBasic
Diluted (in dollars per share)	$ 0.53us-gaap_EarningsPerShareDiluted	$ 0.39us-gaap_EarningsPerShareDiluted	$ 0.46us-gaap_EarningsPerShareDiluted
AVERAGE COMMON SHARES:
Basic (in shares)	43,143	42,607	42,176
Diluted (in shares)	43,409	42,884	42,610

Business Combination, Contingent Consideration Arrangements, Contingent Consideration Benefit

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