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PENSION, POSTRETIREMENT AND OTHER EMPLOYEE BENEFIT PLANS - Pension and Other Postretirement Plan Assets (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | --- | ---
Level 3 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | $ 314 | $ 322 | $ 333
Pension Benefits |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 3,601 | 3,599 | 3,467
Pension Benefits | Level 1 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 106 | 87 |
Pension Benefits | Level 2 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 257 | 501 |
Pension Benefits | Level 3 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 269 | 276 |
Pension Benefits | Assets Measured at NAV |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 2,969 | 2,735 |
Pension Benefits | Equity securities funds |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 1,231 | 1,265 |
Pension Benefits | Equity securities funds | Level 1 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 92 | 74 |
Pension Benefits | Equity securities funds | Level 2 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 4 | 3 |
Pension Benefits | Equity securities funds | Level 3 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 150 | 134 |
Pension Benefits | Equity securities funds | Assets Measured at NAV |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 985 | 1,054 |
Pension Benefits | Fixed-income securities |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 1,359 | 1,325 |
Pension Benefits | Fixed-income securities | Level 1 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Pension Benefits | Fixed-income securities | Level 2 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 100 | 411 |
Pension Benefits | Fixed-income securities | Level 3 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 1 | 3 |
Pension Benefits | Fixed-income securities | Assets Measured at NAV |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 1,258 | 911 |
Pension Benefits | Alternatives |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 762 | 779 |
Pension Benefits | Alternatives | Level 1 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Pension Benefits | Alternatives | Level 2 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Pension Benefits | Alternatives | Level 3 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 116 | 136 |
Pension Benefits | Alternatives | Assets Measured at NAV |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 646 | 643 |
Pension Benefits | Other investments |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 249 | 230 |
Pension Benefits | Other investments | Level 1 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 14 | 13 |
Pension Benefits | Other investments | Level 2 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 153 | 87 |
Pension Benefits | Other investments | Level 3 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 2 | 3 |
Pension Benefits | Other investments | Assets Measured at NAV |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 80 | 127 |
Other Postretirement Benefits |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 45 | 46 | $ 48
Other Postretirement Benefits | Deposit administration fund |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 45 | 46 |
Other Postretirement Benefits | Deposit administration fund | Level 1 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Other Postretirement Benefits | Deposit administration fund | Level 2 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Other Postretirement Benefits | Deposit administration fund | Level 3 |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | 45 | 46 |
Other Postretirement Benefits | Deposit administration fund | Assets Measured at NAV |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Fair value of plan assets | $ 0 | $ 0 |

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