Treasury Stock (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013
Equity, Class of Treasury Stock [Line Items]
Treasury stock purchase plan	$ 40.0
Treasury stock purchase plan remaining available	28.1
Shares Paid for Tax Withholding for Share Based Compensation	43,188
Payments Related to Tax Withholding for Share-based Compensation	$ 3.0
Shares withheld for option exercise in lieu of cash payment	96,927

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.

No definition available.

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