Maximum value of additional common stock to be repurchased authorized by the entity's board of directors, which includes $100 million from the proceeds of notes issued in March 2010.

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury excluding the number of shares employees use to pay the employer who has or will pay the employees' income tax withholding obligations as part of a net-share settlement of share-based awards.

+ Details

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period excluding the value of shares employees use to pay the employer who has or will pay the employees' income tax withholding obligations as part of a net-share settlement of share-based awards. Recorded using the cost method.

+ Details

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- Definition

The amount of adjustment to stockholders' equity associated with an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

+ Details

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- Details

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- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

+ Details

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Data Type:	xbrli:sharesItemType
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- Definition

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

+ Details

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- Definition

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

+ Details

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- Definition

Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28,29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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TREASURY STOCK (Details) (USD $) In Millions, except Share data	3 Months Ended			9 Months Ended
	Sep. 30, 2011	Jun. 30, 2010	Mar. 31, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
TREASURY STOCK.
Remaining amount from all authorization to repurchase common stock	$ 459.2
Repurchase of common shares to satisfy employee withholding tax obligations related to stock-based compensation (in shares)				356,979	84,002
Repurchase of common shares to satisfy employee withholding tax obligations related to stock-based compensation				162.4	19.6
Treasury stock, shares	7,778,107			7,778,107		7,421,128
Additional authorization to repurchase common stock			500
Authorization to repurchase common stock from issuance of 2015 Notes			100
Repurchase of common stock, excluding repurchase of common shares to satisfy employee withholding tax obligations related to stock-based compensation (in shares)		32,487	400,000
Repurchase of common stock, excluding repurchase of common shares to satisfy employee withholding tax obligations related to stock-based compensation		$ 6.1	$ 100.0