Interim Consolidated Statements of Operations (Unaudited) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net sales
Products	$ 412,904us-gaap_SalesRevenueGoodsNet	$ 422,148us-gaap_SalesRevenueGoodsNet
Service	122,797us-gaap_SalesRevenueServicesNet	128,473us-gaap_SalesRevenueServicesNet
Total net sales	535,701us-gaap_SalesRevenueNet	550,621us-gaap_SalesRevenueNet
Cost of sales
Products	164,666us-gaap_CostOfGoodsSold	181,450us-gaap_CostOfGoodsSold
Service	72,230us-gaap_CostOfServices	76,530us-gaap_CostOfServices
Gross profit	298,805us-gaap_GrossProfit	292,641us-gaap_GrossProfit
Research and development	28,461us-gaap_ResearchAndDevelopmentExpense	29,497us-gaap_ResearchAndDevelopmentExpense
Selling, general and administrative	173,038	172,191
Amortization	7,528us-gaap_AmortizationOfDeferredCharges	7,094us-gaap_AmortizationOfDeferredCharges
Interest Expense	6,725us-gaap_InterestExpense	5,666us-gaap_InterestExpense
Restructuring Charges	907us-gaap_RestructuringCharges	1,492us-gaap_RestructuringCharges
Other charges (income), net	(817)us-gaap_OtherNonoperatingIncomeExpense	317us-gaap_OtherNonoperatingIncomeExpense
Earnings before taxes	82,963	76,384
Provision for taxes	19,912us-gaap_IncomeTaxExpenseBenefit	18,333us-gaap_IncomeTaxExpenseBenefit
Net Income (Loss) Attributable to Parent	63,051us-gaap_NetIncomeLoss	58,051us-gaap_NetIncomeLoss
Basic earnings per common share:
Net earnings	$ 2.24us-gaap_EarningsPerShareBasic	$ 1.98us-gaap_EarningsPerShareBasic
Weighted average number of common shares	28,115,220	29,370,232
Diluted earnings per common share:
Net earnings	$ 2.19us-gaap_EarningsPerShareDiluted	$ 1.93us-gaap_EarningsPerShareDiluted
Weighted average number of common and common equivalent shares	28,762,935	30,088,245
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 56,795us-gaap_ComprehensiveIncomeNetOfTax	$ 59,904us-gaap_ComprehensiveIncomeNetOfTax

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