Share Based Compensation (Summary Of Stock Option Activity) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Aug. 31, 2014	Aug. 31, 2013	Aug. 31, 2012
Share Based Compensation [Abstract]
Stock options outstanding, number of stock options	79,138	146,298
Granted, number of stock options	25,394	24,684
Exercised, number of stock options	(15,590)	(89,390)
Forfeitures, number of stock options	(2,319)	(2,454)
Stock options outstanding, number of stock options	86,623	79,138	146,298
Stock options outstanding, average exercise price	$ 53.06	$ 30.97
Granted, average exercise price	$ 76.39	$ 75.68
Exercised, average exercise price	$ 29.21	$ 22.77
Forfeitures, average exercise price	$ 67.55	$ 67.03
Stock options outstanding, averaged exercise price	$ 63.80	$ 53.06	$ 30.97
Average remaining conractual term (years)	7 years 3 months 18 days	6 years 4 months 24 days	3 years 10 months 24 days
Aggregate intrinsic value outstanding	$ 1,817	$ 5,031
Exercised aggregate intrinsic value	853	4,960
Aggregate intrinsic value outstanding	1,211	1,817	5,031
Exercisable number of shares	30,130	31,927	112,987
Exercisable average exercise price	$ 49.55	$ 32.70	$ 22.97
Exercisable average remaining contractual term (years)	5 years 3 months 18 days	3 years	2 years 4 months 24 days
Exercisable intrinsic value	$ 851	$ 1,383	$ 4,789

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Net number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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