Condensed Consolidated Statements of Earnings (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net Sales	$ 185,740us-gaap_SalesRevenueNet	$ 183,979us-gaap_SalesRevenueNet
Cost of Sales	107,659us-gaap_CostOfGoodsAndServicesSold	107,062us-gaap_CostOfGoodsAndServicesSold
Gross Profit	78,081us-gaap_GrossProfit	76,917us-gaap_GrossProfit
Operating Expense:
Research and Development Expense	7,710us-gaap_ResearchAndDevelopmentExpense	7,481us-gaap_ResearchAndDevelopmentExpense
Selling and Administrative Expense	62,117	60,199
Total Operating Expense	69,827us-gaap_OperatingExpenses	67,680us-gaap_OperatingExpenses
Profit from Operations	8,254us-gaap_OperatingIncomeLoss	9,237us-gaap_OperatingIncomeLoss
Other Income (Expense):
Interest Income	50us-gaap_InvestmentIncomeInterest	75us-gaap_InvestmentIncomeInterest
Interest Expense	(377)us-gaap_InterestExpense	(486)us-gaap_InterestExpense
Net Foreign Currency Transaction Losses	(443)	(208)
Other Expense, Net	(52)us-gaap_OtherNonoperatingIncomeExpense	(31)us-gaap_OtherNonoperatingIncomeExpense
Total Other Expense, Net	(822)us-gaap_NonoperatingIncomeExpense	(650)us-gaap_NonoperatingIncomeExpense
Profit Before Income Taxes	7,432	8,587
Income Tax Expense	2,406us-gaap_IncomeTaxExpenseBenefit	2,792us-gaap_IncomeTaxExpenseBenefit
Net Earnings	$ 5,026us-gaap_NetIncomeLoss	$ 5,795us-gaap_NetIncomeLoss
Net Earnings per Share:
Basic	$ 0.27us-gaap_EarningsPerShareBasic	$ 0.32us-gaap_EarningsPerShareBasic
Diluted	$ 0.27us-gaap_EarningsPerShareDiluted	$ 0.31us-gaap_EarningsPerShareDiluted
Weighted Average Shares Outstanding:
Basic	18,283,097	18,318,260
Diluted	18,780,934	18,839,172
Cash Dividend Declared per Common Share	$ 0.20	$ 0.18

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