Employees' Retirement Plans (Details) (USD $) In Millions	12 Months Ended
Aug. 31, 2011	Aug. 31, 2010	Aug. 31, 2009
Deferred Compensation Arrangement With Individual Postretirement Benefits [Line Items]
Compensation expense under defined contribution profit sharing and savings plan and BRP Plan	$ 14.1	$ 19.4	$ 20.8
Unfunded additional liability related to defined employee benefit plans	8.6	8.1
Benefit restoration plan [Member]
Deferred Compensation Arrangement With Individual Postretirement Benefits [Line Items]
Deferred compensation liability	81.2	86.0
Segregated assets	49.4	43.7
Net holding gain (loss) on segregated assets	6.5	3.2	(12.2)
International plan [Member]
Deferred Compensation Arrangement With Individual Postretirement Benefits [Line Items]
Company expenses for international plans	$ 3.2	$ 2.4	$ 2.4

Unfunded Additional Liability Related To Defined Employee Benefit Plans.

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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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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable beyond one year (or the operating cycle, if longer).

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Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

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The amount of the cost recognized during the period for defined contribution plans.

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Amount of net gains or losses recognized during the reporting period on assets that were transferred into separate accounts.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 03-1

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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