Percentage of award that will be paid out in cash upon achievement of performance goals.

No definition available.

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- Definition

Percentage of award that will be paid out in shares of common stock of the Company upon achievement of performance goals.

+ References

No definition available.

+ Details

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- Definition

Percentile on a total stockholder return as compared to peer group based on the average of the closing prices on the principal market for each trading day of a specified period versus those of benchmark period.

+ References

No definition available.

+ Details

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- Definition

Vesting percentage an employees right to exercise share based compensation award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition.

+ References

No definition available.

+ Details

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- Definition

Equivalent number of shares expected to vest under share-based compensation arrangement as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Share based compensation arrangement by share based payment award option expiration.

+ References

No definition available.

+ Details

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- Definition

Equivalent number of shares outstanding under share based compensation arragement.

+ References

No definition available.

+ Details

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- Definition

Percentage of stock based award that will vest upon meeting certain performance conditions.

+ References

No definition available.

+ Details

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph g(1)

-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.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-Subparagraph b

-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.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

-URI http://asc.fasb.org/extlink&oid=6793087&loc=d3e301413-122809

+ Details

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

+ References

+ Details

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The discount rate from market value on offering date that participants pay for shares.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

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).

+ References

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

The total fair value of equity-based awards 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.

+ References

+ Details

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- Definition

The highest quantity of shares an employee can purchase under the plan per period.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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- Definition

The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

+ References

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Share-based Compensation (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Aug. 31, 2012	Aug. 31, 2011	Aug. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 13.1	$ 12.9	$ 13.1
Unrecognized pre-tax compensation cost	22.8
Period of unrecognized pre-tax compensation to be recognized	3 years
Fair value of shares vested	10.7	2.9	3.2
2006 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grants	3,831,278
Vesting period in years	3 years
Vesting Percentage	33.00%
Stock Options and SARs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Option Expiration Date		7 years
2010 RSU Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period in years		4 years
Increment at the end of two years [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Percentage	50.00%
Increment at the end of four years [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Percentage	50.00%
2011 PSU [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period in years	3 years
Payment of award upon achievement of performance goals in share of common stock	50.00%
Payment of award upon achievement of performance goals in Cash	50.00%
2010 PSU [Member] \| Performance Condition One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Condition Vesting Percentage	50.00%
Percentile on Stockholders Return in Peer Group	50th
2010 PSU [Member] \| Performance Condition Second [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Condition Vesting Percentage	100.00%
Percentile on Stockholders Return in Peer Group	60th
1999 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period in years		2 years
Stock Options and SARs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of options and SARs exercised	$ 0.4	$ 7.4	$ 9.8
Share units granted	927,312	112,000	126,000
Restricted Stock Awards And Psus [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards and PSUs Weighted Average Grant-Date Fair Value	$ 10.68	$ 15.55	$ 12.89
Cash settled phantom share units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share units granted	1,132,204
Equivelant number of shares outstanding	1,420,608
Equivalent number of shares expected to vest	1,248,280
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares per employee	400
Purchase discount from market price	15.00%	15.00%	15.00%