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PENSIONS AND OTHER POSTRETIREMENT BENEFITS - Fair Value of Plan Assets (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | --- | ---
Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | $ 4,237 | $ 4,282 | $ 4,338
OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 742 | 739 | 728
Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 1,941 | 1,920 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 450 | 441 |
Significant Other Observable Inputs (Level 2) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 577 | 657 |
Significant Other Observable Inputs (Level 2) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 124 | 121 |
Significant Unobservable Inputs (Level 3) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 692 | 770 | $ 912
Significant Unobservable Inputs (Level 3) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 19 | 27 |
Investments Measured at Net Asset Value | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 1,027 | 935 |
Investments Measured at Net Asset Value | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 149 | 150 |
U.S. equities | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 816 | 809 |
U.S. equities | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 99 | 102 |
U.S. equities | Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 816 | 809 |
U.S. equities | Quoted Prices in Active Markets for Identical Assets (Level 1) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 99 | 102 |
U.S. equities | Significant Other Observable Inputs (Level 2) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
U.S. equities | Significant Other Observable Inputs (Level 2) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
U.S. equities | Significant Unobservable Inputs (Level 3) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
U.S. equities | Significant Unobservable Inputs (Level 3) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
U.S. equities | Investments Measured at Net Asset Value | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
U.S. equities | Investments Measured at Net Asset Value | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Global equities | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 570 | 567 |
Global equities | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 31 | 33 |
Global equities | Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 501 | 502 |
Global equities | Quoted Prices in Active Markets for Identical Assets (Level 1) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 3 | 3 |
Global equities | Significant Other Observable Inputs (Level 2) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Global equities | Significant Other Observable Inputs (Level 2) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Global equities | Significant Unobservable Inputs (Level 3) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Global equities | Significant Unobservable Inputs (Level 3) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Global equities | Investments Measured at Net Asset Value | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 69 | 65 |
Global equities | Investments Measured at Net Asset Value | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 28 | 30 |
U.S. government securities | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 755 | 821 |
U.S. government securities | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 224 | 193 |
U.S. government securities | Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 32 | 22 |
U.S. government securities | Quoted Prices in Active Markets for Identical Assets (Level 1) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 130 | 119 |
U.S. government securities | Significant Other Observable Inputs (Level 2) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 577 | 657 |
U.S. government securities | Significant Other Observable Inputs (Level 2) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 50 | 27 |
U.S. government securities | Significant Unobservable Inputs (Level 3) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
U.S. government securities | Significant Unobservable Inputs (Level 3) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
U.S. government securities | Investments Measured at Net Asset Value | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 146 | 142 |
U.S. government securities | Investments Measured at Net Asset Value | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 44 | 47 |
U.S. corporate bonds | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 698 | 681 |
U.S. corporate bonds | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 342 | 357 |
U.S. corporate bonds | Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 583 | 587 |
U.S. corporate bonds | Quoted Prices in Active Markets for Identical Assets (Level 1) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 216 | 214 |
U.S. corporate bonds | Significant Other Observable Inputs (Level 2) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
U.S. corporate bonds | Significant Other Observable Inputs (Level 2) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 74 | 94 |
U.S. corporate bonds | Significant Unobservable Inputs (Level 3) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
U.S. corporate bonds | Significant Unobservable Inputs (Level 3) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
U.S. corporate bonds | Investments Measured at Net Asset Value | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 115 | 94 |
U.S. corporate bonds | Investments Measured at Net Asset Value | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 52 | 49 |
Non U.S. and other bonds | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 194 | 160 |
Non U.S. and other bonds | Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 9 | 0 |
Non U.S. and other bonds | Significant Other Observable Inputs (Level 2) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Non U.S. and other bonds | Significant Unobservable Inputs (Level 3) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Non U.S. and other bonds | Investments Measured at Net Asset Value | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 185 | 160 |
Hedge funds | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 408 | 403 |
Hedge funds | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 10 | 10 |
Hedge funds | Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Hedge funds | Quoted Prices in Active Markets for Identical Assets (Level 1) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Hedge funds | Significant Other Observable Inputs (Level 2) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Hedge funds | Significant Other Observable Inputs (Level 2) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Hedge funds | Significant Unobservable Inputs (Level 3) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 128 | 118 |
Hedge funds | Significant Unobservable Inputs (Level 3) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 10 | 10 |
Hedge funds | Investments Measured at Net Asset Value | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 280 | 285 |
Hedge funds | Investments Measured at Net Asset Value | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Private equity | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 151 | 146 |
Private equity | Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Private equity | Significant Other Observable Inputs (Level 2) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Private equity | Significant Unobservable Inputs (Level 3) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 151 | 146 |
Private equity | Investments Measured at Net Asset Value | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Structured credit | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 171 | 220 |
Structured credit | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 4 | 7 |
Structured credit | Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Structured credit | Quoted Prices in Active Markets for Identical Assets (Level 1) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Structured credit | Significant Other Observable Inputs (Level 2) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Structured credit | Significant Other Observable Inputs (Level 2) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Structured credit | Significant Unobservable Inputs (Level 3) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 171 | 220 |
Structured credit | Significant Unobservable Inputs (Level 3) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 4 | 7 |
Structured credit | Investments Measured at Net Asset Value | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Structured credit | Investments Measured at Net Asset Value | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Debt Security, Corporate, Non-US | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 2 | 3 |
Debt Security, Corporate, Non-US | Quoted Prices in Active Markets for Identical Assets (Level 1) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 2 | 3 |
Debt Security, Corporate, Non-US | Significant Other Observable Inputs (Level 2) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Debt Security, Corporate, Non-US | Significant Unobservable Inputs (Level 3) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Debt Security, Corporate, Non-US | Investments Measured at Net Asset Value | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Real estate | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 474 | 475 |
Real estate | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 30 | 34 |
Real estate | Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Real estate | Quoted Prices in Active Markets for Identical Assets (Level 1) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Real estate | Significant Other Observable Inputs (Level 2) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Real estate | Significant Other Observable Inputs (Level 2) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 0 | 0 |
Real estate | Significant Unobservable Inputs (Level 3) | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 242 | 286 |
Real estate | Significant Unobservable Inputs (Level 3) | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 5 | 10 |
Real estate | Investments Measured at Net Asset Value | Pension Benefits |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | 232 | 189 |
Real estate | Investments Measured at Net Asset Value | OPEB |  |  |
Defined Benefit Plan, Information about Plan Assets [Abstract] |  |  |
Fair value of pension assets by asset category | $ 25 | $ 24 |

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