Expiration date for the authorization to repurchase up to $1 billion.

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- Definition

Number of shares of common stock that were repurchased in the administration of our employee share-based compensation plans. Under the terms of these plans, we accept shares of common stock from option holders if they elect to surrender previously-owned shares upon exercise of the option to cover the exercise price of the options or, in the case of restricted shares of common stock, the withholding of shares to satisfy tax withholding obligations associated with the vesting of such shares.

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- Definition

Cost of common stock that were repurchased in the administration of our employee share-based compensation plans. Under the terms of these plans, we accept shares of common stock from option holders if they elect to surrender previously-owned shares upon exercise of the option to cover the exercise price of the options or, in the case of restricted shares of common stock, the withholding of shares to satisfy tax withholding obligations associated with the vesting of such shares.

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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 32

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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- Definition

The amount authorized by an entity's Board of Directors under a stock repurchase plan.

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- Definition

The remaining repurchase amount authorized by an entity's Board of Directors under a stock repurchase plan.

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- 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 AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Chapter 1

-Section B

-Paragraph 7

-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.

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-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

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- Definition

Description of share repurchase program authorized by an entity's Board of Directors. Include also the allocation of amounts paid to purchase treasury stock.

+ References

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Chapter 1

-Section B

-Paragraph 11A

-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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

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-Paragraph 2

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-SubTopic 30

-Section 50

-Paragraph 4

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- Definition

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

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Reference 1: 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 AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 10

-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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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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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 FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

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-Paragraph 10

-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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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

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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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Stockholders' Equity (Details) (USD $) In Millions, except Per Share data	1 Months Ended		9 Months Ended
	Oct. 31, 2011	Apr. 30, 2011	Sep. 30, 2011	Sep. 30, 2010	Jun. 30, 2011
Cash dividend declared per share	$ 0.25		$ 0.25		$ 0.25
Expiration date of new authorization			June 30, 2013
Share repurchase authorization		In April 2011, the Board of Directors replaced its previously approved share repurchase authorization of up to $250 million with a new authorization for repurchases of up to $1 billion of our common shares exclusive of shares repurchased in connection with employee stock plans.
Remaining authorized amount under new authorization	$ 561.3
Common shares acquired in connection with employee stock plans, shares			0.8	0.2
Common shares acquired in connection with employee stock plans, amount			48.7	8.2
$1 Billion Authorization [Member]
Shares repurchased			5.90
Value of shares repurchased			438.9
Shares repurchased, average price per share			$ 74.01
Stock Repurchase Program, Authorized Amount		1,000
$ 250 Million Dollar Authorization [Member]
Shares repurchased			0.80	1.99
Value of shares repurchased			52.6	100.0
Shares repurchased, average price per share			$ 63.73	$ 50.17
Stock Repurchase Program, Authorized Amount		250