Note 15 - Income Taxes (Details) - Components of the Provision for Income Taxes (USD $) In Thousands, unless otherwise specified	3 Months Ended
Nov. 30, 2014	Nov. 30, 2013
Current
U.S. Federal	$ 22,704us-gaap_CurrentFederalTaxExpenseBenefit	$ 18,117us-gaap_CurrentFederalTaxExpenseBenefit
U.S. state and local	1,325	1,197
Non-U.S.	1,208us-gaap_CurrentForeignTaxExpenseBenefit	3,187us-gaap_CurrentForeignTaxExpenseBenefit
Total current taxes	25,237us-gaap_CurrentIncomeTaxExpenseBenefit	22,501us-gaap_CurrentIncomeTaxExpenseBenefit
Deferred
U.S. Federal	1,602	311
U.S. state and local	29	28
Non-U.S.	(2,038)	63
Total deferred taxes	(407)us-gaap_DeferredIncomeTaxExpenseBenefit	402us-gaap_DeferredIncomeTaxExpenseBenefit
Total provision for income taxes	$ 24,830us-gaap_IncomeTaxExpenseBenefit	$ 22,903us-gaap_IncomeTaxExpenseBenefit

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