POSTRETIREMENT BENEFIT PLANS - Schedule of Components of Net Benefit Costs (Details) - Principal pension - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Defined Benefit Plan Disclosure [Line Items] | ||||
| Service cost for benefits earned | $ 12 | $ 14 | $ 37 | $ 47 |
| Prior service cost amortization | 0 | (2) | (2) | (7) |
| Expected return on plan assets | (359) | (375) | (1,076) | (1,125) |
| Interest cost on benefit obligations | 310 | 325 | 930 | 976 |
| Net actuarial gain amortization | (109) | (126) | (328) | (379) |
| Net periodic expense (income) | $ (146) | $ (164) | $ (439) | $ (488) |
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Details
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