For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Industry Segment Information (Schedule Of Revenue By Geographical Areas) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Aug. 31, 2018	May 31, 2018	Feb. 28, 2018	Nov. 30, 2017	Aug. 31, 2017	May 31, 2017	Feb. 28, 2017	Nov. 30, 2016	Aug. 31, 2018	Aug. 31, 2017	Aug. 31, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues	$ 123,269	$ 169,571	$ 130,339	$ 124,526	$ 131,937	$ 151,533	$ 124,125	$ 110,390	$ 547,705	$ 517,985	$ 516,411
Revenues [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues									$ 547,705	$ 517,985	$ 516,411
Percentage									100.00%	100.00%	100.00%
Revenues [Member] \| United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues									$ 321,698	$ 297,261	$ 321,554
Percentage									59.00%	57.00%	62.00%
Revenues [Member] \| International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues									$ 226,007	$ 220,724	$ 194,857
Percentage									41.00%	43.00%	38.00%
Long-Lived Tangible Assets [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage									100.00%	100.00%	100.00%
Long-lived tangible assets	57,248				74,498				$ 57,248	$ 74,498	$ 77,627
Long-Lived Tangible Assets [Member] \| United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage									69.00%	73.00%	75.00%
Long-lived tangible assets	39,290				54,199				$ 39,290	$ 54,199	$ 58,098
Long-Lived Tangible Assets [Member] \| International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage									31.00%	27.00%	25.00%
Long-lived tangible assets	$ 17,958				$ 20,299				$ 17,958	$ 20,299	$ 19,529