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Pension and Other Postretirement Benefit Plans - Fair Values of Pension Plan Assets (Details) - Pension Benefits - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | --- | ---
Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 700 | $ 788 |
United States |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 9,717 | 9,804 | $ 9,094
United States | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 164 | 158 |
United States | Developed markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 2,555 | 2,797 |
United States | Emerging markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1,265 | 740 |
United States | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 174 | 113 |
United States | Developed markets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 2,171 | 2,071 |
United States | Government and agency obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 2,101 | 2,307 |
United States | Corporate obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1,293 | 1,485 |
United States | Mortgage and asset-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 21 | 21 |
United States | Derivatives |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | (29) | 109 |
United States | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 2 | 3 |
United States | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 2,355 | 2,438 |
United States | Level 1 | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 43 | 34 |
United States | Level 1 | Developed markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 170 | 224 |
United States | Level 1 | Emerging markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 1 | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 1 | Developed markets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 2,171 | 2,071 |
United States | Level 1 | Government and agency obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 1 | Corporate obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 1 | Mortgage and asset-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 1 | Derivatives |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | (29) | 109 |
United States | Level 1 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 3,415 | 3,813 |
United States | Level 2 | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 2 | Developed markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 2 | Emerging markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 2 | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 2 | Developed markets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 2 | Government and agency obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 2,101 | 2,307 |
United States | Level 2 | Corporate obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1,293 | 1,485 |
United States | Level 2 | Mortgage and asset-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 21 | 21 |
United States | Level 2 | Derivatives |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 2 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 2 | 3 | 4
United States | Level 3 | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 3 | Developed markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 3 | Emerging markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 3 | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 3 | Developed markets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 3 | Government and agency obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 3 | Corporate obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 3 | Mortgage and asset-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 3 | Derivatives |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 3 | Insurance contracts |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 | 0
United States | Level 3 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 2 | 3 | 4
United States | NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 3,945 | 3,550 |
United States | NAV | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 121 | 124 |
United States | NAV | Developed markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 2,385 | 2,573 |
United States | NAV | Emerging markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1,265 | 740 |
United States | NAV | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 174 | 113 |
United States | NAV | Developed markets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | NAV | Government and agency obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | NAV | Corporate obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | NAV | Mortgage and asset-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | NAV | Derivatives |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | NAV | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 9,647 | 9,562 | 8,473
International | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 123 | 118 |
International | Developed markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 4,232 | 3,870 |
International | Emerging markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 145 | 110 |
International | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 12 | 10 |
International | Government and agency obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 3,385 | 3,523 |
International | Corporate obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 180 | 197 |
International | Other fixed income obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 19 | 20 |
International | Developed markets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 287 | 278 |
International | Government and agency obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 368 | 423 |
International | Corporate obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 141 | 160 |
International | Mortgage and asset-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 54 | 61 |
International | Insurance contracts |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 701 | 788 |
International | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 4 |
International | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1,345 | 1,197 |
International | Level 1 | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 112 | 98 |
International | Level 1 | Developed markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 599 | 507 |
International | Level 1 | Emerging markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 54 | 44 |
International | Level 1 | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 1 | Government and agency obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 262 | 234 |
International | Level 1 | Corporate obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 23 | 23 |
International | Level 1 | Other fixed income obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 8 | 9 |
International | Level 1 | Developed markets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 287 | 278 |
International | Level 1 | Government and agency obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 1 | Corporate obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 1 | Mortgage and asset-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 1 | Insurance contracts |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 1 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 4 |
International | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 7,090 | 7,041 |
International | Level 2 | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 2 | Developed markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 3,537 | 3,257 |
International | Level 2 | Emerging markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 2 | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 2 | Government and agency obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 2,974 | 3,123 |
International | Level 2 | Corporate obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 8 | 8 |
International | Level 2 | Other fixed income obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 7 | 8 |
International | Level 2 | Developed markets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 2 | Government and agency obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 368 | 423 |
International | Level 2 | Corporate obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 141 | 160 |
International | Level 2 | Mortgage and asset-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 54 | 61 |
International | Level 2 | Insurance contracts |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1 | 1 |
International | Level 2 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 698 | 785 | 761
International | Level 3 | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 3 | Developed markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 3 | Emerging markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 3 | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 3 | Government and agency obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 3 | Corporate obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 3 | Other fixed income obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 3 | Developed markets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 3 | Government and agency obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 3 | Corporate obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 3 | Mortgage and asset-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | Level 3 | Insurance contracts |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 698 | 785 | 761
International | Level 3 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 | $ 0
International | NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 514 | 539 |
International | NAV | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 11 | 20 |
International | NAV | Developed markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 96 | 106 |
International | NAV | Emerging markets equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 91 | 66 |
International | NAV | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 12 | 10 |
International | NAV | Government and agency obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 149 | 166 |
International | NAV | Corporate obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 149 | 166 |
International | NAV | Other fixed income obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 4 | 3 |
International | NAV | Developed markets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | NAV | Government and agency obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | NAV | Corporate obligations |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | NAV | Mortgage and asset-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
International | NAV | Insurance contracts |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 2 | 2 |
International | NAV | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 0 | $ 0 |

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