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PENSION PLANS (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer contributions | $ 1.2 | $ 1.6 |
After-tax benefit (charge) to shareholders' equity | 11.9 | (37.2) |
Pretax benefit (charge) to shareholders' equity | 16.4 | $ (59.9) | $ (245.9)
Basis point increase (decrease) in the plans' discount rate reflected in benefit (charge) to shareholders' equity - domestic |  | 260 |
Actuarial loss (gain) | 62.0 | $ (669.8) |
Benefit obligation | 2,148.2 | 2,119.5 | 2,888.3
Projected benefit payments [Abstract] |  |  |
Par outstanding value of bonds used to determine the discount rate yield curve | $ 250.0 |  |
Historic rate of return on plan assets in the last 5 year period | 6.70% |  |
Historic rate of return on plan assets in the last 10 year period | 6.70% |  |
Historic rate of return on plan assets in the last 15 year period | 7.80% |  |
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment | $ (7.5) | 0.0 |
Qualified plans |  |  |
Projected benefit payments [Abstract] |  |  |
2023 | 152.2 |  |
2024 | 143.6 |  |
2025 | 137.8 |  |
2026 | 132.3 |  |
2027 | 126.0 |  |
Non-qualified plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Benefit obligation | 3.7 | 4.2 |
Projected benefit payments [Abstract] |  |  |
2023 | 0.6 |  |
2024 | 0.4 |  |
2025 | 0.4 |  |
2026 | 0.3 |  |
2027 | $ 0.2 |  |
U.S. |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Basis point increase (decrease) in the plans' discount rate reflected in benefit (charge) to shareholders' equity - domestic | 30 |  |
U.S. | Pension Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer contributions | $ 0.2 | 0.2 |
Actuarial loss (gain) | 47.1 | (556.1) |
Benefit obligation | $ 1,871.1 | $ 1,868.4 | $ 2,506.0
Projected benefit payments [Abstract] |  |  |
Discount rate—periodic benefit cost | 5.50% | 2.90% | 2.40%
Expected return on plans’ assets | 6.75% | 6.75% | 7.25%
Rate of compensation increase | 3.00% | 3.00% | 3.00%
Discount rate—benefit obligation | 5.20% | 5.50% | 2.90%
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment | $ 0.0 | $ 0.0 |
Foreign |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Basis point increase/decrease in the plans' discount rate reflected in charge to shareholders' equity - international | (50) | 230 |
Foreign | Pension Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer contributions | $ 1.0 | $ 1.4 |
Actuarial loss (gain) | 14.9 | (113.7) |
Benefit obligation | $ 277.1 | $ 251.1 | $ 382.3
Projected benefit payments [Abstract] |  |  |
Discount rate—periodic benefit cost | 3.70% | 1.40% | 0.80%
Expected return on plans’ assets | 4.40% | 3.80% | 4.20%
Rate of compensation increase | 3.40% | 3.00% | 3.00%
Discount rate—benefit obligation | 3.20% | 3.70% | 1.40%
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment | $ (7.5) | $ 0.0 |
Foreign | Qualified plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer contributions | 1.0 | $ 1.3 | $ 1.1
Foreign | Qualified plans | Maximum |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year | $ 5.0 |  |

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- Definition Aftertax change in the value of either the benefit obligation or the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption, or the consequence of a decision to temporarily deviate from the substantive plan, that has not been recognized in net periodic benefit cost. + References No definition available. + Details
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