Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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-Section S99

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Share Based Compensation (Details Textual) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term			4 years 8 months 12 days
Share-based compensation expense	$ 3.2	$ 3.1	$ 6.1	$ 6.2
Tax benefit from share-based compensation expense	$ 1.2	$ 1.2	$ 2.3	$ 2.3
Stock Option SAR Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted during period			341,800
Restricted Stock and Performance Share Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted during period			65,850
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted during period			61,740
Phantom Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted during period			5,617