BENEFIT PLANS - PENSION BENEFITS AND OTHER POSTRETIREMENT BENEFITS RECOGNIZED IN THE ACCOMPANYING CONSOLIDATED BALANCE SHEETS (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Deferred tax asset	$ 27.0	$ 42.9
Current liabilities	(4.2)	(4.8)
Other noncurrent liabilities	(232.7)	(288.5)
Deferred tax liability	(0.8)	(0.5)
Total liabilities	(237.7)	(293.8)
Accumulated other comprehensive income	71.5	111.8
Net amount recognized	(139.2)	(139.1)
Other Postretirement Benefit Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Deferred tax asset	0.9	1.2
Current liabilities	(0.7)	(0.6)
Other noncurrent liabilities	(13.4)	(13.3)
Deferred tax liability	0.0	0.0
Total liabilities	(14.1)	(13.9)
Accumulated other comprehensive income	1.5	1.8
Net amount recognized	$ (11.7)	$ (10.9)