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Retirement Plans - Schedule of Plan Asset Measured on a Recurring Basis (Details) - Pension Plan - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | $ 4,068 | $ 4,400 | $ 4,363
Fair Value, Recurring |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | 4,068 | 4,400 |
Fair Value, Recurring | Federal government securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | 1,448 | 1,508 |
Fair Value, Recurring | Bonds and debentures |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | 1,512 | 1,696 |
Fair Value, Recurring | Corporate stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | 226 | 181 |
Fair Value, Recurring | Venture capital and buyout partnerships |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | $ 446 | $ 554 |
Defined Benefit Plan, Plan Assets, Fair Value by Hierarchy and NAV [Extensible Enumeration] | Fair Value Measured at Net Asset Value Per Share | Fair Value Measured at Net Asset Value Per Share |
Fair Value, Recurring | Real estate funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | $ 26 | $ 30 |
Defined Benefit Plan, Plan Assets, Fair Value by Hierarchy and NAV [Extensible Enumeration] | Fair Value Measured at Net Asset Value Per Share | Fair Value Measured at Net Asset Value Per Share |
Fair Value, Recurring | Collective trust and other funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | $ 370 | $ 382 |
Defined Benefit Plan, Plan Assets, Fair Value by Hierarchy and NAV [Extensible Enumeration] | Fair Value Measured at Net Asset Value Per Share | Fair Value Measured at Net Asset Value Per Share |
Fair Value, Recurring | Other assets/(liabilities) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | $ 40 | $ 49 |
Fair Value, Recurring | Fair Value, Inputs, Level 1, Level 2, and Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | 3,186 | 3,385 |
Fair Value, Recurring | Quoted Prices in Active Markets for Identical Inputs (Level 1) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | 220 | 176 |
Fair Value, Recurring | Quoted Prices in Active Markets for Identical Inputs (Level 1) | Federal government securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | 0 | 0 |
Fair Value, Recurring | Quoted Prices in Active Markets for Identical Inputs (Level 1) | Bonds and debentures |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | 0 | 0 |
Fair Value, Recurring | Quoted Prices in Active Markets for Identical Inputs (Level 1) | Corporate stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | 220 | 176 |
Fair Value, Recurring | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | 2,966 | 3,209 |
Fair Value, Recurring | Significant Other Observable Inputs (Level 2) | Federal government securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | 1,448 | 1,508 |
Fair Value, Recurring | Significant Other Observable Inputs (Level 2) | Bonds and debentures |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | 1,512 | 1,696 |
Fair Value, Recurring | Significant Other Observable Inputs (Level 2) | Corporate stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | 6 | 5 |
Fair Value, Recurring | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | 0 | 0 |
Fair Value, Recurring | Significant Unobservable Inputs (Level 3) | Federal government securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | 0 | 0 |
Fair Value, Recurring | Significant Unobservable Inputs (Level 3) | Bonds and debentures |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | 0 | 0 |
Fair Value, Recurring | Significant Unobservable Inputs (Level 3) | Corporate stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | 0 | 0 |
Fair Value, Recurring | Fair Value Measured at Net Asset Value Per Share |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total plan assets | $ 842 | $ 966 |

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