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v3.24.2

Pensions and Other Postretirement Benefits - Narrative (Details) $ in Millions | 3 Months Ended | 5 Months Ended | 6 Months Ended
--- | --- | --- | ---
Jun. 30, 2024 USD ($) | Jun. 30, 2023 USD ($) | May 31, 2024 employee | Jun. 30, 2024 USD ($) | Jun. 30, 2023 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Expected number of positions eliminated | employee |  |  | 350 |  |
Pension Benefits |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Curtailment gain | $ 0 | $ 0 |  | $ 0 | $ 0
Other Postretirement Benefits |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Curtailment gain | $ 20 | $ 0 |  | $ 20 | $ 0
Percent reduction in future years of service of plan participants (more than) | 10.00% |  |  |  |
Benefit obligation discount rate | 5.74% |  |  | 5.74% |
Reduction to benefit obligation | $ 11 |  |  |  |

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