Annual report pursuant to Section 13 and 15(d)

BENEFIT PLANS - Narrative (Details)

v3.20.4
BENEFIT PLANS - Narrative (Details)
$ in Millions
 12 Months Ended
Dec. 31, 2020
USD ($)
plan
trust
shares
Dec. 31, 2019
USD ($)
shares
Dec. 31, 2018
USD ($)
Defined Benefit Plan Disclosure [Line Items]      
Number of executive defined benefit pension plans | plan 3    
Number of executive retirement programs | plan 3    
Accumulated benefit obligation $ 765.9 $ 712.4  
Recognized actuarial loss (gain ) - mark to market $ (32.2) 4.8  
Hedge funds, minimum number of days notice prior to redemption 30 days    
Hedge funds, maximum number of days notice prior to redemption 90 days    
Maximum portfolio invested in securities (as a percent) 5.00%    
Maximum equity portfolio's market value invested in securities (as a percent) 10.00%    
Cost recognized $ 31.8 26.9 $ 30.7
Accrued incentive compensations $ 149.0 $ 77.7  
Number of employee benefit trusts for the purpose of satisfying obligations under Supplemental Retirement Plans | trust 2    
Number of supplemental retirement plans | plan 2    
Stock held by employee benefit trusts (in shares) | shares 600,000 600,000  
Amount held in employee benefit trusts $ 5.9 $ 5.9  
Minimum      
Defined Benefit Plan Disclosure [Line Items]      
Discretionary match of participants' contributions, dependent on certain eligibility rules 500.00%    
Maximum      
Defined Benefit Plan Disclosure [Line Items]      
Discretionary match of participants' contributions, dependent on certain eligibility rules 600.00%    
Pension Benefits      
Defined Benefit Plan Disclosure [Line Items]      
Employer contributions $ 6.7 6.0  
Recognized actuarial loss (gain ) - mark to market $ (30.4) (0.2) (7.7)
Pension Benefits | U.S.      
Defined Benefit Plan Disclosure [Line Items]      
Defined benefit plan percentage of employees covered 10.00%    
Employer contributions $ 0.0 0.0  
Pension Benefits | Non-U.S. Defined Benefit Plans      
Defined Benefit Plan Disclosure [Line Items]      
Employer contributions   0.2  
Other Postretirement Benefit Plans      
Defined Benefit Plan Disclosure [Line Items]      
Employer contributions 1.5 1.6  
Plan assets in excess of projected benefit obligation and accumulated benefit obligation, plan assets 585.3 554.0  
Plan assets in excess of projected benefit obligation and accumulated benefit obligation, projected benefit obligation 588.4 552.9  
Plan assets in excess of projected benefit obligation and accumulated benefit obligation, accumulated benefit obligation 588.4 552.9  
Recognized actuarial loss (gain ) - mark to market (1.8) 5.0 (0.4)
Other Postretirement Benefit Plans | U.S.      
Defined Benefit Plan Disclosure [Line Items]      
Plans with projected benefit obligations and accumulated benefits benefit obligations in excess of plan's respective assets, projected benefit obligation 115.6 108.4  
Plans with projected benefit obligations and accumulated benefits benefit obligations in excess of plan's respective assets, accumulated benefit obligation $ 115.0 108.3  
Initial annual rate increase in the per capita cost of covered healthcare benefits 6.50%    
Ultimate annual rate decrease in the per capita cost of covered healthcare benefits 5.00%    
Approved target allocation (as a percent) 80.00%    
Approved target allocation for return seeking assets (as a percent) 20.00%    
Other Postretirement Benefit Plans | Non-U.S. Defined Benefit Plans      
Defined Benefit Plan Disclosure [Line Items]      
Plans with projected benefit obligations and accumulated benefits benefit obligations in excess of plan's respective assets, projected benefit obligation $ 62.4 58.7  
Plans with projected benefit obligations and accumulated benefits benefit obligations in excess of plan's respective assets, accumulated benefit obligation   51.2  
Plans with projected benefit obligations and accumulated benefits benefit obligations in excess of plan's respective assets, fair value of plan assets $ 53.1 49.3  
Initial annual rate increase in the per capita cost of covered healthcare benefits 5.00%    
Cost recognized $ 13.4 $ 13.9 $ 14.1