Share-based Compensation (Shares Subject to Options and SARs Excluding the Cash Components) (Details) (Options and SARs excluding cash components [Member], USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Nov. 30, 2012
Options and SARs excluding cash components [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options and SARs, outstanding, number, beginning balance	2,930,492
Options and SARs, granted, number	175,298
Options and SARs, forfeited / expired, number	(34,602)
Options and SARs, outstanding, number, ending balance	3,071,188
Options and SARs, exercisable, number	2,076,475
Options and SARs, outstanding, weighted average exercise price, beginning balance	$ 24.81
Options and SARs, granted, weighted average exercise price	$ 14.12
Options and SARs, forfeited / expired, weighted average exercise price	$ 25.94
Options and SARs, outstanding, weighted average exercise price, ending balance	$ 24.19
Options and SARs, exercisable, weighted average exercise price	$ 29.86
Options and SARs, outstanding, weighted average remaining contractual life (years)	3 years 3 months
Options and SARs, exercisable, weighted average remaining contractual life (years)	1 year 11 months
Options and SARs, outstanding, aggregated intrinsic value	$ 1,814,963
Options and SARs, exercisable, aggregated intrinsic value	$ 266,884

Share-based Compensation (Shares Subject to Options and SARs Excluding the Cash Components) (Details) (Options and SARs excluding cash components [Member], USD $)
In Thousands, except Share data, unless otherwise specified

3 Months Ended

Nov. 30, 2012

Options and SARs excluding cash components [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Options and SARs, outstanding, number, beginning balance

2,930,492

Options and SARs, granted, number

175,298

Options and SARs, forfeited / expired, number

(34,602)

Options and SARs, outstanding, number, ending balance

3,071,188

Options and SARs, exercisable, number

2,076,475

Options and SARs, outstanding, weighted average exercise price, beginning balance

$ 24.81

Options and SARs, granted, weighted average exercise price

$ 14.12

Options and SARs, forfeited / expired, weighted average exercise price

$ 25.94

Options and SARs, outstanding, weighted average exercise price, ending balance

$ 24.19

Options and SARs, exercisable, weighted average exercise price

$ 29.86

Options and SARs, outstanding, weighted average remaining contractual life (years)

3 years 3 months

Options and SARs, exercisable, weighted average remaining contractual life (years)

1 year 11 months

Options and SARs, outstanding, aggregated intrinsic value

$ 1,814,963

Options and SARs, exercisable, aggregated intrinsic value

$ 266,884

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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.

+ References

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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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For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including 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 grantees can acquire the shares reserved for issuance on stock options awarded.

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