Derivative Financial Instruments and Hedging Activities - Fair Value of Derivative Instruments Recorded on Consolidated Statements of Operations (Details) - Cost of revenue - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Feb. 28, 2019	Feb. 28, 2018	Feb. 28, 2019	Feb. 28, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Foreign currency losses	$ 57,100	$ 41,700	$ 52,600	$ 35,500
Forward foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain Recognized in Net Income on Derivatives	$ 49,794	$ 48,933	$ 42,808	$ 45,744

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6450222&loc=d3e30840-110895

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: 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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