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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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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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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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Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of tax effect from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act.

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Basis Of Presentation And Summary Of Significant Accounting Policies (Narrative) (Details) - USD ($)	3 Months Ended		9 Months Ended
	May 31, 2019	May 31, 2018	May 31, 2019	May 31, 2018	Nov. 30, 2018	Aug. 31, 2018	Nov. 30, 2017
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Unrealized foreign currency transactions			$ 658,000	$ 200,000
Carrying value of senior notes	$ 61,208,000		61,208,000			$ 62,800,000
Cumulative effect of change in accounting principle					$ (324,000)		$ 61,000
Foreign Currency Forward Contracts [Member]
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Foreign currency forward contracts outstanding	10,300,000		$ 10,300,000
Foreign currency forward contracts, Maturity date			Jun. 30, 2019
Realized foreign currency transactions	400,000	$ 0	$ 0	400,000
Unrealized foreign currency transactions			0	$ 0
Level 2 [Member] \| Recurring [Member]
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Assets	0		0
Liabilities	0		0
Level 2 [Member] \| Nonrecurring [Member]
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Assets	0		0
Liabilities	0		0
Senior Notes [Member]
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Fair value of senior notes	19,000,000.0		19,000,000.0
Carrying value of senior notes	18,800,000		18,800,000
Accounting Standards Update 2018-02 [Member]
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Reclassification from AOCI to retained earnings	100,000
Retained Earnings [Member]
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Cumulative effect of change in accounting principle	$ 98,000		$ 98,000		$ (324,000)		$ (128,000)