STOCK-BASED COMPENSATION - Components of Stock Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 12.4	$ 7.5
Tax benefits on stock-based compensation expense	5.1	3.9
To be settled with stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	10.1	4.6
Employee contributions for above stock plans	2.3	2.9
Total stock-based compensation	12.4	7.5
Tax benefits on stock-based compensation expense	2.5	1.1
To be settled with stock \| Tax benefits on stock-based compensation payments
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Tax benefits on stock-based compensation expense	2.6	2.8
To be settled with stock \| Stock-based retirement plans contributions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	1.4	(0.3)
To be settled with stock \| Deferred Stock Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	0.4	0.5
To be settled with stock \| Stock-based retirement plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	0.3	0.2
To be settled with stock \| Discount Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	0.2	0.3
To be settled with stock \| PSU - TSR based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	0.8	0.9
To be settled with stock \| PSU - E B I T C A G R based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	1.7	(2.1)
To be settled with stock \| Prior PSU awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	0.0	0.0
To be settled with stock \| Restricted Stock Unit (RSU) awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	5.3	4.7
To be settled with stock \| Other, primarily non-employee directors restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	0.0	0.4
To be settled in cash
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	2.6	(5.4)
To be settled in cash \| Stock-based retirement plans contributions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	0.1	0.1
To be settled in cash \| Deferred Stock Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	0.0	0.0
To be settled in cash \| Stock-based retirement plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	0.0	0.0
To be settled in cash \| Discount Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	0.0	0.0
To be settled in cash \| PSU - TSR based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	0.3	(2.8)
To be settled in cash \| PSU - E B I T C A G R based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	2.2	(2.8)
To be settled in cash \| Prior PSU awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	0.0	0.1
To be settled in cash \| Restricted Stock Unit (RSU) awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	0.0	0.0
To be settled in cash \| Other, primarily non-employee directors restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense (income)	$ 0.0	$ 0.0

Employee contributions to stock compensation plans.

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