PENSION PLANS (Details 8) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 2,469.1	$ 2,199.3	$ 1,993.0
Investments Measured at Net Asset Value
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	1,567.2	1,469.5
Quoted Prices In Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	396.3	267.0
Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	505.6	462.8
Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
U.S. equities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	318.6	250.0
U.S. equities | Investments Measured at Net Asset Value
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	85.0	117.2
U.S. equities | Quoted Prices In Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	233.6	132.8
U.S. equities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
U.S. equities | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Non-U.S. equities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	422.6	374.2
Non-U.S. equities | Investments Measured at Net Asset Value
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	382.3	341.2
Non-U.S. equities | Quoted Prices In Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	39.9	32.7
Non-U.S. equities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.4	0.3
Non-U.S. equities | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Cash
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	122.8	101.5
Cash | Investments Measured at Net Asset Value
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Cash | Quoted Prices In Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	122.8	101.5
Cash | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Cash | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Government treasuries
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	419.9	285.0
Government treasuries | Investments Measured at Net Asset Value
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Government treasuries | Quoted Prices In Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Government treasuries | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	419.9	285.0
Government treasuries | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Corporate debt instruments
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	176.7	257.4
Corporate debt instruments | Investments Measured at Net Asset Value
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	114.6	99.1
Corporate debt instruments | Quoted Prices In Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Corporate debt instruments | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	62.1	158.3
Corporate debt instruments | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	149.5	186.1
Asset-backed securities | Investments Measured at Net Asset Value
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	126.3	166.9
Asset-backed securities | Quoted Prices In Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Asset-backed securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	23.2	19.2
Asset-backed securities | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Hedge fund of funds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	817.8	698.3
Hedge fund of funds | Investments Measured at Net Asset Value
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	817.8	698.3
Hedge fund of funds | Quoted Prices In Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Hedge fund of funds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Hedge fund of funds | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Real estate funds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	9.0	16.9
Real estate funds | Investments Measured at Net Asset Value
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	9.0	16.9
Real estate funds | Quoted Prices In Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Real estate funds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Real estate funds | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Private equity funds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	32.2	29.9
Private equity funds | Investments Measured at Net Asset Value
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	32.2	29.9
Private equity funds | Quoted Prices In Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Private equity funds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.0	0.0
Private equity funds | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 0.0	$ 0.0