STOCK-BASED COMPENSATION - Components of Stock Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 9.7	$ 12.9
Tax benefits on stock-based compensation expense	2.3	3.2
To be settled with stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	8.2	10.4
Employee contributions for above stock plans	1.5	2.5
Total stock-based compensation	9.7	12.9
Tax benefits on stock-based compensation expense	2.0	2.6
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	0.3	0.6
To be settled with stock \| Executive Stock Unit (ESU) program contributions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.7	1.2
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	0.3	0.4
To be settled with stock \| ESU program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.2	0.4
To be settled with stock \| Discount Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.2	0.2
To be settled with stock \| 2023 PSU awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.4	0.0
To be settled with stock \| 2022 and prior PSU awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.7	1.0
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	5.3	6.7
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	0.4	0.5
To be settled in cash
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.8	0.0
To be settled in cash \| Executive Stock Unit (ESU) program contributions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.1	0.2
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	0.0	0.0
To be settled in cash \| ESU program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	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	0.0	0.0
To be settled in cash \| 2023 PSU awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.4	0.0
To be settled in cash \| 2022 and prior PSU awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-related compensation expense	0.3	(0.2)
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	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	$ 0.0	$ 0.0

Employee contributions to stock compensation plans.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Amount of noncash expense for share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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