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Amount of cash outflow to satisfy an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

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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.

+ References

No definition available.

+ Details

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- Definition

Number of stock bought back by the entity at the exercise price or redemption price.

+ References

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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- Definition

Equity impact of the value of stock bought back by the entity at the exercise price or redemption price.

+ References

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- Definition

Amount of a stock repurchase plan authorized by an entity's Board of Directors.

+ References

No definition available.

+ Details

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- Definition

Amount remaining of a stock repurchase plan authorized by an entity's Board of Directors.

+ References

No definition available.

+ Details

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Stock Repurchases (Details Textual) (USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended	6 Months Ended		12 Months Ended
	Dec. 31, 2011	Jun. 30, 2013	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012 2012 Share Repurchase Plan [Member]
Equity, Class of Treasury Stock [Line Items]
Authorized amount for share repurchase	$ 700.0				$ 300.0
Remaining authorized amount for share repurchase		338.2
Shares Paid for Tax Withholding for Share Based Compensation			0.1
Payments Related to Tax Withholding for Share-based Compensation			5.8	2.6
Shares repurchased			0.5
Stock Redeemed or Called During Period, Value			$ 33.0