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Final price paid per share for the purchase of the targeted number of shares, determined by an average market price over a fixed period of time.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 25

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6405686&loc=d3e22802-112653

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- Definition

Amount of cash receipt from (payment to) bank; or stock received from (issuance to) bank in the settlement of the accelerated share repurchase agreement.

+ References

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

+ 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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-SubTopic 30

-Section 45

-Paragraph 1

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

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Share Repurchase Program (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	6 Months Ended	1 Months Ended
	Feb. 28, 2015	Jan. 31, 2015	Oct. 31, 2014	Feb. 28, 2015	Aug. 31, 2014
Share Repurchase Program [Line Items]
Shares repurchase authorized amount					$ 105.0
Shares acquired through stock repurchase program	2.9us-gaap_TreasuryStockSharesAcquired
Purchase of treasury stock	95.3
Remaining amount authorized for repurchase through share repurchase program	9.7			9.7
October 2014 Accelerated Share Repurchase Program [Member]
Share Repurchase Program [Line Items]
Shares repurchase authorized amount			15.0
Shares acquired through stock repurchase program		0	0.6
Purchase of treasury stock			15.0
Cash payment at completion of accelerated share repurchase program		0.1
Final price paid per share		$ 26.32
February 2015 Accelerated Share Repurchase Program [Member]
Share Repurchase Program [Line Items]
Shares repurchase authorized amount	75.0			75.0
Shares acquired through stock repurchase program				2.1
Purchase of treasury stock				$ 75.0