Benefit Plans: (Narrative) (Details) - 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] | ||||
| Employer contributions | $ 100 | |||
| Anticipated additional employer contributions during the remainder of the current fiscal year | $ 44 | 44 | ||
| Cash refunds of surplus assets | 682 | |||
| Pension Plan | ||||
| Defined Benefit Plan Disclosure [Line Items] | ||||
| Settlement loss, pre tax | 74 | $ 0 | 74 | $ 0 |
| Settlement loss, net of tax | 65 | $ 65 | ||
| Benefit obligation transferred to insurer at settlement date | $ 1,000 | |||
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- Definition Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due To Settlement, Net Of Tax No definition available.
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- Definition Defined Benefit Plan, Plan Assets, Surplus Assets Refunds No definition available.
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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 contribution expected to be received by defined benefit plan from employer in remainder of current fiscal year. Excludes contribution previously paid by employer in current fiscal year. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of (increase) decrease to benefit obligation of defined benefit plan from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Includes, but is not limited to, lump-sum cash payment to participant in exchange for right to receive specified benefits, purchase of nonparticipating annuity contract and change from remeasurement. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Details
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