Name:	us-gaap_EquityClassOfTreasuryStockLineItems
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Data Type:	xbrli:stringItemType
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The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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Data Type:	xbrli:sharesItemType
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Period Type:	instant

- Definition

The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

Name:	us-gaap_StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

+ Details

Name:	us-gaap_TreasuryStockAcquiredAverageCostPerShare
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

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Period Type:

Capital Stock and Share Repurchase Share Repurchase (Details) (USD $)	6 Months Ended	12 Months Ended			30 Months Ended	42 Months Ended
	Feb. 28, 2015	Aug. 31, 2014	Aug. 31, 2013	Aug. 31, 2012	Feb. 28, 2015	Feb. 28, 2015	Mar. 16, 2015
Equity, Class of Treasury Stock [Line Items]
Treasury Stock, Shares, Acquired	6,241,158us-gaap_TreasuryStockSharesAcquired	8,211,846us-gaap_TreasuryStockSharesAcquired	1,324,762us-gaap_TreasuryStockSharesAcquired	2,658,751us-gaap_TreasuryStockSharesAcquired	18,436,517us-gaap_TreasuryStockSharesAcquired
Treasury Stock Acquired, Average Cost Per Share	$ 28.90	$ 34.52	$ 31.55	$ 23.70		$ 30.84
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased	2,563,483				2,563,483	2,563,483
Subsequent Event [Member]
Equity, Class of Treasury Stock [Line Items]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased							7,000,000