Note 5 - Derivative Instruments (Details Textual) ₨ in Billions	12 Months Ended
Aug. 31, 2017 USD ($)	Aug. 31, 2016 USD ($)	Aug. 31, 2017 INR (₨)
Gain (Loss) on Discontinuation of Foreign Currency Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring, Net	$ 0	$ 0
Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivative Asset, Notional Amount	51,000,000	91,690,000	₨ 3.8
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred	$ 3,800,000
India, Rupees
Percent of Foreign Exchange Contracts Hedged	75.00%
India, Rupees \| Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivative Asset, Notional Amount	$ 51,000,000	$ 58,410,000

Represents the percent of foreign exchange contracts hedged.

No definition available.

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- Definition

Nominal or face amount used to calculate payments on the derivative asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5580258-113959

+ Details

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- Definition

The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

+ References

No definition available.

+ Details

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- Definition

The amount of net gain (loss) reclassified into earnings when foreign currency cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

+ Details

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