Note 15 - Income Taxes (Details) - Provision for Income Taxes by Geographic Operations (USD $) In Thousands, unless otherwise specified	3 Months Ended
Nov. 30, 2014	Nov. 30, 2013
Provision for Income Taxes by Geographic Operations [Abstract]
U.S. operations	$ 65,958	$ 60,258
Non-U.S. operations	14,732	14,823
Income before income taxes	80,690	75,081
U.S. operations	25,660	19,653
Non-U.S. operations	(830)	3,250
Total provision for income taxes	$ 24,830us-gaap_IncomeTaxExpenseBenefit	$ 22,903us-gaap_IncomeTaxExpenseBenefit
Effective tax rate	30.80%	30.50%

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

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Amount of current and deferred federal income tax expense (benefit) attributable to income (loss) from continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Glossary Income Tax Expense (or Benefit)

-URI http://asc.fasb.org/extlink&oid=6515339

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-Publisher FASB

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-Topic 235

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Amount of current and deferred foreign income tax expense (benefit) attributable to income (loss) from continuing operations.

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The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

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Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

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-Paragraph 1

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Topic 740

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