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Pension and Other Postretirement Benefits - Narrative (Details) - USD ($) $ in Millions | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Oct. 31, 2021 | Mar. 31, 2021 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Restructuring and other charges |  |  |  | $ 56 | $ 90 | $ 182
Average duration for plans' projected cash flows |  |  |  | 10 years |  |
Period expected long-term rate of return is applied |  |  |  | 5 years |  |
Expected long-term rate of return on plan assets |  |  |  | 6.70% | 6.20% | 6.00%
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%
Rate to which the cost trend rate gradually declines |  |  |  | 4.50% | 4.50% | 4.50%
Pension contributions |  |  |  | $ 43 | $ 96 | $ 257
Expenses related to defined contribution plan |  |  |  | $ 76 | 66 | 73
Minimum |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Rate to which the cost trend rate gradually declines |  |  |  | 1.80% |  |
Maximum |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Rate to which the cost trend rate gradually declines |  |  |  | 11.30% |  |
Scenario, forecast |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Contribution next fiscal year |  |  | $ 45 |  |  |
Pension benefits |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Restructuring and other charges | $ 34 |  |  |  |  | 69
Decrease in postretirement benefits liability | $ 125 |  |  |  |  |
Curtailment (charge) benefit |  |  |  | $ 0 | (6) | 0
Other postretirement benefits |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Decrease in postretirement benefits liability |  | $ 39 |  |  |  | 6
Curtailment (charge) benefit |  |  |  | $ 0 | 0 | 2
Number of years over actual annual healthcare cost trend experience |  |  |  | 3 years |  |
United States |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Pension contributions |  |  |  | $ 43 | 96 |
Payment for pension benefit plan in excess of minimum required |  |  |  |  | 12 |
United States | Scenario, forecast |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Expected long-term rate of return on plan assets |  |  | 7.00% |  |  |
Contribution next fiscal year |  |  | $ 35 |  |  |
United States | Other postretirement benefits |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Curtailment (charge) benefit |  |  |  |  | $ 23 | 66
Percent reduction of plan participants |  |  |  |  | 70.00% |
Foreign Plan | Other postretirement benefits |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Decrease in postretirement benefits liability |  |  |  | 2 |  |
Pension Settlement Cost |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Restructuring and other charges |  |  |  | 17 | $ 12 | $ 8
Pension Settlement Cost | United States |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Restructuring and other charges |  |  |  | $ 41 |  |

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