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Pension and Other Postretirement Benefits - Narrative (Details) - USD ($) $ in Millions | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2023 | Dec. 31, 2022 | Oct. 31, 2021 | Jul. 31, 2023 | Jun. 30, 2023 | Dec. 31, 2021 | Mar. 31, 2021 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Change in accrued other postretirement benefits liability |  |  |  | $ 10 |  |  |  |  |  |  |
Settlements |  |  |  |  |  |  |  |  | $ 5 | $ 58 | $ 75
Average duration for plans' projected cash flows (in years) |  |  |  |  |  |  |  |  | 10 years |  |
Period expected long-term rate of return is applied (in years) |  |  |  |  |  |  |  |  | 5 years |  |
Expected long-term rate of return on plan assets |  |  |  |  |  |  |  |  | 6.70% | 6.70% | 6.20%
Number of years over actual annual healthcare cost trend experience |  |  |  |  |  |  |  |  | 20 years |  |
Health care cost trend rate assumed for next year |  | 5.50% |  |  |  | 5.50% |  |  | 5.50% | 5.50% | 5.50%
Defined benefit plan, ultimate health care cost trend rate |  | 4.50% |  |  |  | 4.50% |  |  | 4.50% | 4.50% | 4.50%
Pension contributions |  |  |  |  |  |  |  |  | $ 36 | $ 43 | $ 96
Contribution next fiscal year |  |  |  |  |  |  |  |  | 52 |  |
Expenses related to defined contribution plan |  |  |  |  |  |  |  |  | $ 82 | 76 | 66
Minimum |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Defined benefit plan, ultimate health care cost trend rate |  |  |  |  |  |  |  |  | (0.40%) |  |
Maximum |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Defined benefit plan, ultimate health care cost trend rate |  |  |  |  |  |  |  |  | 11.30% |  |
United States |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Pension contributions |  |  |  |  |  |  |  |  | $ 36 | 43 |
Contribution next fiscal year |  |  |  |  |  |  |  |  | 45 |  |
United States | Scenario, forecast |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Expected long-term rate of return on plan assets |  |  |  |  |  |  |  | 7.00% |  |  |
Pension benefits paid |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Restructuring and other (credits) charges |  |  |  |  |  | $ 34 |  |  |  |  |
Increase (decrease) in obligation, pension benefits |  |  | $ 125 |  |  |  |  |  |  |  |
Settlements |  |  |  |  | $ 3 |  |  |  | 5 | 58 | 69
Pension benefits paid | United States |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Increase (decrease) in obligation, pension benefits | $ 19 |  |  |  |  |  |  |  |  |  |
Settlements |  |  |  |  |  |  |  |  |  | 41 |
Pension benefits paid | Canada |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Increase (decrease) in obligation, pension benefits |  | $ 2 |  |  |  |  |  |  |  |  |
Pension benefits paid | United Kingdom |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Settlements |  |  |  |  |  |  |  |  |  |  | 23
Other postretirement benefits |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Increase (decrease) in obligation, pension benefits |  |  |  |  |  |  | $ 39 |  |  |  |
Settlements |  |  |  |  |  |  |  |  | $ 0 | 0 | 0
Number of years over actual annual healthcare cost trend experience |  |  |  |  |  |  |  |  | 3 years |  |
Pension Settlement Cost |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Restructuring and other (credits) charges |  |  |  |  |  |  |  |  | $ 2 | $ 17 | $ 12

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