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

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Date the derivative contract matures, in CCYY-MM-DD format.

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

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

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Fair value of financial and nonfinancial obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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.

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Basis of Presentation and Summary of Significant Accounting Policies

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Basis Of Presentation And Summary Of Significant Accounting Policies (Narrative) (Details) - USD ($)	3 Months Ended
	Nov. 30, 2018	Nov. 30, 2017	Aug. 31, 2018
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Foreign currency forward contracts outstanding	$ 24,900,000
Foreign currency forward contracts, Maturity date	Dec. 01, 2018
Realized foreign currency transactions	$ 0	$ 300,000
Impairment of long-lived assets	0
Unrealized net losses	210,000	150,000
Excess tax benefits	2,839,000	3,926,000
Carrying value of senior notes	62,400,000		$ 62,800,000
Foreign Currency Forward Contracts [Member]
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Unrealized net losses	0	$ 0
Level 2 [Member] \| Recurring [Member]
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Assets	0
Liabilities	0
Level 2 [Member] \| Nonrecurring [Member]
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Assets	0
Liabilities	0
Senior Notes [Member]
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Fair value of senior notes	18,000,000
Carrying value of senior notes	$ 19,200,000