POSTRETIREMENT BENEFIT PLANS - Narrative (Details) - USD ($) $ in Millions |
1 Months Ended | 3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|---|
Jun. 30, 2026 |
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Defined Benefit Plan Disclosure [Line Items] | |||||
| Defined contribution plan costs | $ 41 | $ 33 | $ 139 | $ 119 | |
| Principal retiree benefit | |||||
| Defined Benefit Plan Disclosure [Line Items] | |||||
| Expected future premiums | 375 | 375 | |||
| Premiums paid | 353 | ||||
| Net actuarial gains/(losses) and prior service credits | 293 | ||||
| Curtailment / settlement loss (gain) | 84 | 1 | 84 | 1 | |
| Principal pension | |||||
| Defined Benefit Plan Disclosure [Line Items] | |||||
| Curtailment / settlement loss (gain) | $ 0 | $ 0 | $ 0 | $ 0 | |
| Defined benefit plan, contributions by employer | $ 516 | ||||
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- Definition Defined Benefit Plan Expected Future Employer Contributions In Next Twelve Months No definition available.
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- Definition Defined Benefit Plan Payments For Annuity Contracts No definition available.
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- Definition Amount of gain (loss), recognized immediately as component of net periodic benefit (cost) credit, for change in value of benefit obligation or plan assets from experience different from that assumed, change in actuarial assumption, or consequence of temporarily deviating from substantive plan. Includes, but is not limited to, amount in excess of 10 percent of greater of fair value of plan assets or benefit obligation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. 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 gain (loss) recognized in net periodic benefit (cost) credit from settlement and curtailment. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. No definition available.
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- Details
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- Details
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