Note 20 - Risks and Concentrations of Credit Risk (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Aug. 31, 2018	Aug. 31, 2017
Investments and Cash, Total	$ 237,900
Long-term Debt, Fair Value	575,000
Allowance for Doubtful Accounts Receivable, Ending Balance	$ 3,500	$ 2,700
Subscription Revenue [Member]
Concentration Risk, Percentage	2.00%
Revolving Credit Facility [Member] \| The Loan [Member]
Interest Expense, Debt, Total	$ 15,900	$ 8,400
Hypothetical Basis Point Change, LIBOR Rate	0.25%
Change in Annual Interest Expense	$ 1,400
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate	1.00%

Represents the amount of change in annual interest expense related to specific interest changes.

No definition available.

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- Definition

The hypothetical basis point change in the London Interbank Offered Rate (LIBOR).

+ References

No definition available.

+ Details

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- Definition

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

+ References

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- Definition

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.

+ References

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
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- Definition

Sum of investments and unrestricted cash as of the balance sheet date.

+ References

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-Name Accounting Standards Codification
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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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