PENSION AND POST-RETIREMENT BENEFITS Saving Plans, Pension and Post Retirement Benefits - Summary of Unrecognized Components of Net Periodic Benefit Cost (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax	$ 280.1
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Prior Service Cost (Credit), before Tax	0
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax	280.1
Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Tax	(43.6)
Defined Benefit Plan Accumulated Other Comprehensive Income Loss After Tax Portion Attributable To Related Party	(1.2)
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax	235.3
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax	277.6
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Prior Service Cost (Credit), before Tax	0
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax	277.6	170.1
Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Tax	(43.7)	(1.8)
Defined Benefit Plan Accumulated Other Comprehensive Income Loss After Tax Portion Attributable To Related Party	(1.0)	(0.7)
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax	232.9	167.6
Other Post-Retirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax	2.5
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Prior Service Cost (Credit), before Tax	0
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax	2.5	2.8
Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Tax	0.1	0.1
Defined Benefit Plan Accumulated Other Comprehensive Income Loss After Tax Portion Attributable To Related Party	(0.2)	0
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax	$ 2.4	$ 2.9