Derivative Instruments - Fair Values of Derivative Instruments (Detail) - USD ($) $ in Thousands	Feb. 28, 2018	Aug. 31, 2017
Designated as Hedging Instrument \| Accounts Receivable
Derivatives, Fair Value [Line Items]
Asset Derivatives	$ 2,756	$ 2,341
Designated as Hedging Instrument \| Accounts Payable and Accrued Liabilities
Derivatives, Fair Value [Line Items]
Liability Derivatives	686	2,886
Designated as Hedging Instrument \| Foreign Exchange Contracts \| Accounts Receivable
Derivatives, Fair Value [Line Items]
Asset Derivatives	2,158	2,341
Designated as Hedging Instrument \| Foreign Exchange Contracts \| Accounts Payable and Accrued Liabilities
Derivatives, Fair Value [Line Items]
Liability Derivatives	685	1,761
Designated as Hedging Instrument \| Interest rate swap contracts \| Accounts Receivable
Derivatives, Fair Value [Line Items]
Asset Derivatives	598
Designated as Hedging Instrument \| Interest rate swap contracts \| Accounts Payable and Accrued Liabilities
Derivatives, Fair Value [Line Items]
Liability Derivatives	1	1,125
Not Designated as Hedging Instrument \| Foreign Exchange Contracts \| Accounts Receivable
Derivatives, Fair Value [Line Items]
Asset Derivatives	1,722	$ 1,473
Not Designated as Hedging Instrument \| Foreign Exchange Contracts \| Accounts Payable and Accrued Liabilities
Derivatives, Fair Value [Line Items]
Liability Derivatives	$ 30

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

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.

+ References

No definition available.

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