Stock Repurchases (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Equity, Class of Treasury Stock [Line Items]
Authorized amount for share repurchase	$ 700.0
Remaining authorized amount for share repurchase	246.2
Shares Paid for Tax Withholding for Share Based Compensation	0.1
Payments Related to Tax Withholding for Share-based Compensation	$ 10.7	$ 4.2

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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

+ 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.

+ References

No definition available.

+ Details

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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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