EARNINGS PER SHARE (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Computation of Basic Income per Share [Abstract]
Net income	$ 43.7	$ 47.6	$ 84.2	$ 86.3
Basic shares (in shares)	80.2	80.1	80.2	80.1
Basic net income per share (in dollars per share)	$ 0.54	$ 0.59	$ 1.05	$ 1.08
Computation of Diluted Income per Share [Abstract]
Basic shares (in shares)	80.2	80.1	80.2	80.1
Stock-based compensation (in shares)	1.0	0.6	1.0	0.7
Diluted shares (in shares)	81.2	80.7	81.2	80.8
Diluted net income per share (in dollars per share)	$ 0.54	$ 0.59	$ 1.04	$ 1.07
Antidilutive shares excluded from the computation of earnings per share (in shares)	0.6	1.8	1.4	0.8