STOCK-BASED COMPENSATION – STOCK-BASED COMPENSATION EXPENSE (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Information related to share based awards
Total stock-based compensation expense	$ 4.2	$ 3.5
Deferred income tax benefit	1.7	1.4
Stock-based compensation cost capitalized	0	0
Stock options
Information related to share based awards
Total stock-based compensation expense	0	0.3
Performance stock rights
Information related to share based awards
Total stock-based compensation expense	0.6	0.5
Restricted Share Units
Information related to share based awards
Total stock-based compensation expense	3.4	2.5
Nonemployee director deferred stock units
Information related to share based awards
Total stock-based compensation expense	$ 0.2	$ 0.2

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

-SubTopic 10

-Section 50

-Paragraph 1

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-Name Accounting Standards Codification

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

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

+ References

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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

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

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