Stock-based Compensation (Schedule Of Restricted Stock Units Activity) (Details) - Restricted Stock Units [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Aug. 31, 2019	Aug. 31, 2018	Aug. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding, Number of Shares	115,308
Granted, Number of Shares	17,562
Converted to common shares, Number of Shares	(35,813)
Forfeited, Number of Shares	(137)
Outstanding, Number of Shares	96,920	115,308
Vested, Number of Shares	72,069
Outstanding, Weighted-Average Grant Date Fair Value Per Share	$ 70.52
Granted, Weighted-Average Grant Date Fair Value Per Share	163.93	$ 111.71	$ 109.23
Converted to common shares, Weighted-Average Grant Date Fair Value Per Share	74.19
Forfeited, Weighted-Average Grant Date Fair Value Per Share	130.99
Outstanding, Weighted-Average Grant Date Fair Value Per Share	86.01	$ 70.52
Vested, Weighted-Average Grant Date Fair Value Per Share	$ 70.34
Outstanding, Aggregate Intrinsic Value	$ 17,669
Vested, Aggregate Intrinsic Value	$ 13,138

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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-Topic 718
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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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-Publisher FASB
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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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.

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Intrinsic value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Intrinsic value of equity-based compensation awards vested. Excludes stock and unit options.

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested, Weighted Average Grant Date Fair Value

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