Note J - Income Taxes (Details) - Income Tax Expense Components (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current:
Federal	$ 13,383us-gaap_CurrentFederalTaxExpenseBenefit	$ 15,154us-gaap_CurrentFederalTaxExpenseBenefit	$ 7,730us-gaap_CurrentFederalTaxExpenseBenefit
State	3,151	3,247	1,328
Foreign	3,563us-gaap_CurrentForeignTaxExpenseBenefit	1,651us-gaap_CurrentForeignTaxExpenseBenefit	1,184us-gaap_CurrentForeignTaxExpenseBenefit
	20,097us-gaap_CurrentIncomeTaxExpenseBenefit	20,052us-gaap_CurrentIncomeTaxExpenseBenefit	10,242us-gaap_CurrentIncomeTaxExpenseBenefit
Deferred:
Federal	3,264	2,523	10,977
State	399	323	2,550
Foreign	360	(2)	67
	4,023us-gaap_DeferredIncomeTaxExpenseBenefit	2,844us-gaap_DeferredIncomeTaxExpenseBenefit	13,594us-gaap_DeferredIncomeTaxExpenseBenefit
Income Tax Expense	$ 24,120us-gaap_IncomeTaxExpenseBenefit	$ 22,896us-gaap_IncomeTaxExpenseBenefit	$ 23,836us-gaap_IncomeTaxExpenseBenefit

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