Derivative Financial Instruments and Hedging Activities (Foreign Currency Risk Management) (Details) - USD ($) $ in Millions	12 Months Ended
Aug. 31, 2018	Aug. 31, 2017
Cost of revenue
Derivative [Line Items]
Foreign currency losses	$ 29.6
Forward foreign exchange contracts \| Cost of revenue
Derivative [Line Items]
Gain recognized due to changes in fair value of derivatives	48.7
Forward contracts \| Cash flow hedging
Derivative [Line Items]
Aggregate notional amount	3,400.0	$ 2,100.0
Forward contracts \| Forward foreign exchange contracts
Derivative [Line Items]
Aggregate notional amount	$ 293.4	$ 314.6

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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+ References

No definition available.

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- Definition

Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=109240200&loc=d3e30690-110894

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-Name Accounting Standards Codification
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-Section 50
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Aggregate gain on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
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-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

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