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.

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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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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).

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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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Industry Segment Information (Schedule of Revenue by Geographical Areas) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Aug. 31, 2019	May 31, 2019	Feb. 28, 2019	Nov. 30, 2018	Aug. 31, 2018	May 31, 2018	Feb. 28, 2018	Nov. 30, 2017	Aug. 31, 2019	Aug. 31, 2018	Aug. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues	$ 101,885	$ 121,054	$ 109,182	$ 111,951	$ 123,269	$ 169,571	$ 130,339	$ 124,526	$ 444,072	$ 547,705	$ 517,985
Revenues [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues									$ 444,072	$ 547,705	$ 517,985
Percentage									100.00%	100.00%	100.00%
Revenues [Member] \| United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues									$ 257,719	$ 321,698	$ 297,261
Percentage									58.00%	59.00%	57.00%
Revenues [Member] \| International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues									$ 186,353	$ 226,007	$ 220,724
Percentage									42.00%	41.00%	43.00%
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	68,968				57,248				$ 68,968	$ 57,248	$ 74,498
Long-Lived Tangible Assets [Member] \| United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage									76.00%	69.00%	73.00%
Long-lived tangible assets	52,187				39,290				$ 52,187	$ 39,290	$ 54,199
Long-Lived Tangible Assets [Member] \| International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage									24.00%	31.00%	27.00%
Long-lived tangible assets	$ 16,781				$ 17,958				$ 16,781	$ 17,958	$ 20,299