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Pension and Other Postretirement Benefits - Schedule of Fair Value of Pension Plan Assets (Details) - Pension benefits - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | $ 886 | $ 925 | $ 970
Securities purchased and sold but not yet settled |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 875 | 960 |
Equities: |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 563 | 436 |
Equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 431 | 310 |
Long/short equity hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 20 | 18 |
Private equity |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 112 | 108 |
Fixed income |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 212 | 419 |
Intermediate and long duration government/credit |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 128 | 350 |
Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 84 | 69 |
Other investments: |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 100 | 105 |
Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 55 | 73 |
Discretionary and systematic macro hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 40 | 29 |
Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 5 | 3 |
Securities purchased and sold but not yet settled, asset (liability) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 11 | (35) |
Level 1 | Securities purchased and sold but not yet settled |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 90 | 205 |
Level 1 | Equities: |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 1 | 0 |
Level 1 | Equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 1 | 0 |
Level 1 | Long/short equity hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 0 | 0 |
Level 1 | Private equity |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 0 | 0 |
Level 1 | Fixed income |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 89 | 205 |
Level 1 | Intermediate and long duration government/credit |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 71 | 199 |
Level 1 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 18 | 6 |
Level 1 | Other investments: |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 0 | 0 |
Level 1 | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 0 | 0 |
Level 1 | Discretionary and systematic macro hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 0 | 0 |
Level 1 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 0 | 0 |
Level 2 | Securities purchased and sold but not yet settled |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 254 | 304 |
Level 2 | Equities: |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 130 | 85 |
Level 2 | Equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 130 | 85 |
Level 2 | Long/short equity hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 0 | 0 |
Level 2 | Private equity |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 0 | 0 |
Level 2 | Fixed income |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 123 | 214 |
Level 2 | Intermediate and long duration government/credit |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 57 | 151 |
Level 2 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 66 | 63 |
Level 2 | Other investments: |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 1 | 5 |
Level 2 | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 1 | 5 |
Level 2 | Discretionary and systematic macro hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 0 | 0 |
Level 2 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 0 | 0 |
Net Asset Value | Securities purchased and sold but not yet settled |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 531 | 451 |
Net Asset Value | Equities: |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 432 | 351 |
Net Asset Value | Equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 300 | 225 |
Net Asset Value | Long/short equity hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 20 | 18 |
Net Asset Value | Private equity |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 112 | 108 |
Net Asset Value | Fixed income |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 0 | 0 |
Net Asset Value | Intermediate and long duration government/credit |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 0 | 0 |
Net Asset Value | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 0 | 0 |
Net Asset Value | Other investments: |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 99 | 100 |
Net Asset Value | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 54 | 68 |
Net Asset Value | Discretionary and systematic macro hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | 40 | 29 |
Net Asset Value | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net plan assets | $ 5 | $ 3 |

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