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Investment And Other Income (loss), Net (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Investment And Other Income (loss), Net [Abstract] |  |  |  |
Investment and other income, net increase (decrease) | $ (38) | $ (16) | $ (63) |
Increase (decrease) in post-retirement remeasurement loss |  |  | 14 |
OPEB remeasurement gain (loss) | 0 | (21) | (8) | $ 6
Pension benefit reduction | (2) |  | 11 |
Pension building sale (loss) | (19) |  | (19) |
Pension remeasurement gain (loss) | $ 0 | $ 23 | 44 | $ 25
Increase in pension remeasurement gain |  |  | $ 19 |

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- Definition Investment And Other Nonoperating Income Expense Net Increase Decrease + References No definition available. + Details
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- Definition Amount of increase (decrease) in obligation for pension benefits. Includes, but is not limited to, defined benefit or defined contribution plans. Excludes other postretirement benefits. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (a) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-28 + Details
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