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Benefit Plans (Tables) | 12 Months Ended
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Dec. 31, 2023
Benefit Plans [Abstract] |
Pension Obligation and Funded Status | The following table set forth Company’s pension obligation and funded status at December 31:
|  | Pension Benefits |  |  | Post-Retirement Benefits |
(millions of dollars) |  | 2023 |  |  | 2022 |  |  | 2023 |  |  | 2022 |
Change in benefit obligations: |  |  |  |  |  |  |  |  |  |  |  |
Beginning projected benefit obligation |  | $ | 348.9 |  |  | $ | 495.0 |  |  | $ | 1.8 |  |  | $ | 2.3 |
Service cost |  |  | 4.5 |  |  |  | 6.6 |  |  |  | — |  |  |  | — |
Interest cost |  |  | 16.0 |  |  |  | 11.0 |  |  |  | 0.1 |  |  |  | — |
Actuarial loss (gain) |  |  | 11.4 |  |  |  | (124.2 | ) |  |  | 0.1 |  |  |  | (0.4 | )
Benefits paid |  |  | (15.0 | ) |  |  | (12.4 | ) |  |  | — |  |  |  | (0.1 | )
Settlements |  |  | (0.5 | ) |  |  | (18.4 | ) |  |  | — |  |  |  | — |
Foreign exchange impact |  |  | 3.3 |  |  |  | (9.0 | ) |  |  | — |  |  |  | — |
Other |  |  | 0.3 |  |  |  | 0.3 |  |  |  | — |  |  |  | — |
Ending projected benefit obligation |  |  | 368.9 |  |  |  | 348.9 |  |  |  | 2.0 |  |  |  | 1.8 |
Change in plan assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning fair value |  |  | 285.4 |  |  |  | 381.4 |  |  |  | — |  |  |  | — |
Actual return (loss) on plan assets |  |  | 34.4 |  |  |  | (61.6 | ) |  |  | — |  |  |  | — |
Employer contributions |  |  | 9.9 |  |  |  | 9.0 |  |  |  | — |  |  |  | 0.1 |
Plan participants’ contributions |  |  | 0.3 |  |  |  | 0.3 |  |  |  | — |  |  |  | — |
Benefits paid |  |  | (15.0 | ) |  |  | (12.4 | ) |  |  | — |  |  |  | (0.1 | )
Settlements |  |  | (0.5 | ) |  |  | (24.2 | ) |  |  | — |  |  |  | — |
Foreign exchange impact |  |  | 2.9 |  |  |  | (7.1 | ) |  |  | — |  |  |  | — |
Ending fair value |  |  | 317.4 |  |  |  | 285.4 |  |  |  | — |  |  |  | — |
Funded status |  | $ | (51.5 | ) |  | $ | (63.5 | ) |  | $ | (2.0 | ) |  | $ | (1.8 | )
Amounts Recognized in Consolidated Balance Sheet | Amounts recognized in the consolidated balance sheet consist of:
| Pension Benefits |  | Post-Retirement Benefits |
(millions of dollars) | 2023 |  | 2022 |  | 2023 |  | 2022 |
Current liability |  | $ | (1.8 | ) |  | $ | (1.7 | ) |  | $ | (0.1 | ) |  | $ | (0.1 | )
Non-current liability |  |  | (49.7 | ) |  |  | (61.8 | ) |  |  | (1.9 | ) |  |  | (1.7 | )
Recognized liability |  | $ | (51.5 | ) |  | $ | (63.5 | ) |  | $ | (2.0 | ) |  | $ | (1.8 | )
Amounts Recognized in Accumulated Other Comprehensive Loss | Amounts recognized in accumulated other comprehensive loss, net of related tax effects, consist of:
| Pension Benefits |  | Post-Retirement Benefits |
(millions of dollars) | 2023 |  | 2022 |  | 2023 |  | 2022 |
Net actuarial (gain) loss |  | $ | 32.0 |  |  | $ | 38.0 |  |  | $ | (3.3 | ) |  | $ | (3.8 | )
Prior service cost |  |  | 0.1 |  |  |  | 0.1 |  |  |  | — |  |  |  | — |
Amount recognized end of year |  | $ | 32.1 |  |  | $ | 38.1 |  |  | $ | (3.3 | ) |  | $ | (3.8 | )
Change in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income | Changes in the Plan assets and benefit obligations recognized in other comprehensive income:
| Pension Benefits |  | Post-Retirement Benefits |
(millions of dollars) | 2023 |  | 2022 |  | 2023 |  | 2022 |
Current year actuarial gain (loss) |  | $ | 3.8 |  |  | $ | 31.2 |  |  | $ | (0.1 | ) |  | $ | 0.4 |
Amortization of actuarial (gain) loss |  |  | 2.2 |  |  |  | 4.0 |  |  |  | (0.3 | ) |  |  | (0.3 | )
Total recognized in other comprehensive income |  | $ | 6.0 |  |  | $ | 35.2 |  |  | $ | (0.4 | ) |  | $ | 0.1 |
Net Periodic Benefit Cost | The components of net periodic benefit costs are as follows:
|  | Pension Benefits |  |  | Post-Retirement Benefits |
(millions of dollars) |  | 2023 |  |  | 2022 |  |  | 2021 |  |  | 2023 |  |  | 2022 |  |  | 2021 |
Service cost |  | $ | 4.5 |  |  | $ | 6.6 |  |  | $ | 7.7 |  |  | $ | — |  |  | $ | — |  |  | $ | 0.1 |
Interest cost |  |  | 16.0 |  |  |  | 11.0 |  |  |  | 7.9 |  |  |  | 0.1 |  |  |  | — |  |  |  | 0.1 |
Expected return on plan assets |  |  | (17.8 | ) |  |  | (21.5 | ) |  |  | (22.0 | ) |  |  | — |  |  |  | — |  |  |  | — |
Recognized net actuarial (gain) loss |  |  | 2.9 |  |  |  | 5.3 |  |  |  | 12.1 |  |  |  | (0.5 | ) |  |  | (0.4 | ) |  |  | (0.8 | )
Settlement/curtailment (gain) loss |  |  | 0.1 |  |  |  | 3.5 |  |  |  | 3.4 |  |  |  | — |  |  |  | — |  |  |  | (1.6 | )
Net periodic benefit cost |  | $ | 5.7 |  |  | $ | 4.9 |  |  | $ | 9.1 |  |  | $ | (0.4 | ) |  | $ | (0.4 | ) |  | $ | (2.2 | )
Weighted Average Assumptions Used to Determine Net Periodic Benefit Cost and Benefit Obligation | The weighted average assumptions used to determine net periodic benefit cost in the accounting for the pension benefit plans and other benefit plans for the years ended December 31, 2023, 2022 and 2021 are as follows:
|  | Year Ended December 31, |
|  | 2023 |  |  | 2022 |  |  | 2021 |
Discount rate |  |  | 4.84 | % |  |  | 4.30 | % |  |  | 2.01 | %
Expected return on plan assets |  |  | 6.53 | % |  |  | 6.34 | % |  |  | 6.28 | %
Rate of compensation increase |  |  | 2.77 | % |  |  | 2.74 | % |  |  | 2.72 | %
Interest crediting rate |  |  | 2.25 | % |  |  | 2.25 | % |  |  | 2.25 | %
The weighted average assumptions used to determine benefit obligations for the pension benefit plans and other benefit plans at December 31, 2023, 2022 and 2021 are as follows:
| Year Ended December 31, |
| 2023 |  | 2022 |  | 2021 |
Discount rate |  |  | 4.63 | % |  |  | 4.84 | % |  |  | 2.42 | %
Rate of compensation increase |  |  | 2.76 | % |  |  | 2.76 | % |  |  | 2.74 | %
Weighted Average Asset Allocation Percentages | The Company’s pension plan weighted average asset allocation percentages at December 31, 2023 and 2022 by asset category are as follows:
|  | December 31, |
|  | 2023 |  |  | 2022 |
Asset Category |  |  |  |  |  |
Equity securities |  |  | 51.3 | % |  |  | 54.3 | %
Fixed income securities |  |  | 35.3 | % |  |  | 32.2 | %
Real estate |  |  | 0.3 | % |  |  | 0.3 | %
Other |  |  | 13.1 | % |  |  | 13.2 | %
Total |  |  | 100.0 | % |  |  | 100.0 | %
Fair Value of Plan Assets | The Company’s pension plan fair values at December 31, 2023 and 2022 by asset category are as follows:
|  | December 31, |
(millions of dollars) |  | 2023 |  |  | 2022 |
Asset Category |  |  |  |  |  |
Equity securities |  | $ | 162.9 |  |  | $ | 155.0 |
Fixed income securities |  |  | 112.0 |  |  |  | 91.9 |
Real estate |  |  | 0.8 |  |  |  | 0.8 |
Other |  |  | 41.7 |  |  |  | 37.7 |
Total |  | $ | 317.4 |  |  | $ | 285.4 |
The following table presents domestic and foreign pension plan assets information at December 31, 2023, 2022 and 2021 (the measurement date of pension plan assets):
| U.S. Plans |  | International Plans |
(millions of dollars) | 2023 |  | 2022 |  | 2021 |  | 2023 |  | 2022 |  | 2021 |
Fair value of plan assets |  | $ | 251.4 |  |  | $ | 226.4 |  |  | $ | 293.8 |  |  | $ | 66.0 |  |  | $ | 59.0 |  |  | $ | 87.6 |
Defined Benefit Pension Plan Assets Measured at Fair Value | The following table summarizes our defined benefit pension plan assets measured at fair value as of December 31, 2023:
|  | Quoted Prices in Active Markets for Identical Assets |  |  | Significant Other Observable Inputs |  |  | Significant Unobservable Inputs |  |  |  |
(millions of dollars) |  | (Level 1) |  |  | (Level 2) |  |  | (Level 3) |  |  | Total |
Pension Assets Fair Value as of December 31, 2023 |  |  |  |  |  |  |  |  |  |  |  |
Equity securities |  |  |  |  |  |  |  |  |  |  |  |
US equities |  | $ | 142.5 |  |  | $ | — |  |  | $ | — |  |  | $ | 142.5 |
Non-US equities |  |  | 20.4 |  |  |  | — |  |  |  | — |  |  |  | 20.4 |
Fixed income securities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Corporate debt instruments |  |  | 98.0 |  |  |  | 14.0 |  |  |  | — |  |  |  | 112.0 |
Real estate and other |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Real estate |  |  | — |  |  |  | — |  |  |  | 0.8 |  |  |  | 0.8 |
Other |  |  | 0.4 |  |  |  | 35.0 |  |  |  | 6.3 |  |  |  | 41.7 |
Total assets |  | $ | 261.3 |  |  | $ | 49.0 |  |  | $ | 7.1 |  |  | $ | 317.4 |
The following table summarizes our defined benefit pension plan assets measured at fair value as of December 31, 2022:
|  | Quoted Prices in Active Markets for Identical Assets |  |  | Significant Other Observable Inputs |  |  | Significant Unobservable Inputs |  |  |  |
(millions of dollars) |  | (Level 1) |  |  | (Level 2) |  |  | (Level 3) |  |  | Total |
Pension Assets Fair Value as of December 31, 2022 |  |  |  |  |  |  |  |  |  |  |  |
Equity securities |  |  |  |  |  |  |  |  |  |  |  |
US equities |  | $ | 135.7 |  |  | $ | — |  |  | $ | — |  |  | $ | 135.7 |
Non-US equities |  |  | 19.3 |  |  |  | — |  |  |  | — |  |  |  | 19.3 |
Fixed income securities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Corporate debt instruments |  |  | 79.6 |  |  |  | 12.3 |  |  |  | — |  |  |  | 91.9 |
Real estate and other |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Real estate |  |  | — |  |  |  | — |  |  |  | 0.8 |  |  |  | 0.8 |
Other |  |  | 0.3 |  |  |  | 30.6 |  |  |  | 6.8 |  |  |  | 37.7 |
Total assets |  | $ | 234.9 |  |  | $ | 42.9 |  |  | $ | 7.6 |  |  | $ | 285.4 |
Reconciliation of Changes in Fair Value Measurement of Plan Assets Using Significant Unobservable Inputs | The following is a reconciliation of changes in fair value measurement of plan assets using significant unobservable inputs (Level 3):
(millions of dollars) |  |  |
Beginning balance at December 31, 2021 |  | $ | 6.0 |
Purchases, sales, settlements |  |  | — |
Actual return on plan assets still held at reporting date |  |  | 1.8 |
Foreign exchange impact |  |  | (0.2 | )
Ending balance at December 31, 2022 |  | $ | 7.6 |
Purchases, sales, settlements |  |  | — |
Actual (loss) return on plan assets still held at reporting date |  |  | (0.6 | )
Foreign exchange impact |  |  | 0.1 |
Ending balance at December 31, 2023 |  | $ | 7.1 |
Estimated Future Benefit Payments | The following benefit payments, which reflect expected future service, as appropriate, are expected to be paid:
(millions of dollars) |  | Pension Benefits |  |  | Other Benefits |
2024 |  | $ | 23.9 |  |  | $ | 0.1 |
2025 |  | $ | 24.0 |  |  | $ | 0.1 |
2026 |  | $ | 24.8 |  |  | $ | 0.2 |
2027 |  | $ | 25.5 |  |  | $ | 0.2 |
2028 |  | $ | 25.9 |  |  | $ | 0.2 |
2029-2033 |  | $ | 123.9 |  |  | $ | 0.9 |

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