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PENSION AND OTHER POST-EMPLOYMENT BENEFITS - Narrative (Details) - USD ($) $ in Millions |  |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | --- | ---
May 13, 2023 | May 12, 2023 | Jun. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |
Defined benefit plan, assumptions used calculating benefit obligation, increase (decrease) in discount rate |  |  | 0.29% |  |
Employee benefit plan funding and related payments |  |  |  | $ (44) | $ (39)
Pension |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |
Voluntary cash contribution |  | $ 750 |  |  |
Discount rate | 8.00% |  |  |  |
Expected future contributions |  | $ 260 |  |  |
Pension and OPEB mark-to -market adjustment |  |  | $ 59 | $ 0 | $ 59

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- Definition Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Increase (Decrease) in Discount Rate + References No definition available. + Details
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- Definition Defined Benefit Plan, Expected Future Employer Contributions, Next Five Years + References No definition available. + Details
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- Definition Pension And Other Postretirement Benefits, Contributions And Related Payments + References No definition available. + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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