PENSION AND POST-RETIREMENT BENEFITS - Aggregate Reconciliation of Projected Benefit Obligations, Plan Assets, Funded Status and Amounts Recognized (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Change in Benefit Obligation:
Benefit obligation - beginning of year	$ (661.4)
Benefit obligation - end of year	(591.0)	$ (661.4)
Change in Plan Assets:
Fair value of plan assets - beginning of year	497.2
Fair value of plan assets - end of year	432.4	497.2
Pension Plans
Change in Benefit Obligation:
Benefit obligation - beginning of year	(661.4)	(640.5)
Service cost	(2.0)	(3.0)
Interest cost	(18.6)	(19.6)
Actuarial gain (loss)	42.0	(22.3)
Curtailment gain	0.0	3.3
Other pension settlements	0.0	3.6
Benefits paid	45.2	43.2
Other	0.0	(18.4)
Plan participant contributions	(0.6)	(0.7)
Foreign currency translation adjustments	4.4	(7.0)
Benefit obligation - end of year	(591.0)	(661.4)
Change in Plan Assets:
Fair value of plan assets - beginning of year	497.2	464.0
Actual return on plan assets	(24.2)	53.5
Employer contributions	8.0	7.6
Other pension settlements	0.0	(3.6)
Benefits paid	(45.2)	(43.2)
Other	0.0	11.6
Plan participant contributions	0.6	0.7
Foreign currency translation adjustments	(4.0)	6.6
Fair value of plan assets - end of year	432.4	497.2
Total liability	(158.6)	(164.2)
Other Post-Retirement Benefit Plans
Change in Benefit Obligation:
Benefit obligation - beginning of year	(14.0)	(13.4)
Service cost	0.0	0.0
Interest cost	(0.4)	(0.4)
Actuarial gain (loss)	1.4	(1.1)
Curtailment gain	0.0	0.0
Other pension settlements	0.0	0.0
Benefits paid	0.8	0.9
Other	0.0	0.0
Plan participant contributions	0.0	0.0
Foreign currency translation adjustments	0.0	0.0
Benefit obligation - end of year	(12.2)	(14.0)
Change in Plan Assets:
Fair value of plan assets - beginning of year	0.0	0.0
Actual return on plan assets	0.0	0.0
Employer contributions	0.8	0.9
Other pension settlements	0.0	0.0
Benefits paid	(0.8)	(0.9)
Other	0.0
Plan participant contributions	0.0
Foreign currency translation adjustments	0.0	0.0
Fair value of plan assets - end of year	0.0	0.0
Total liability	$ (12.2)	$ (14.0)