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Investment And Other Income, Net (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Investment And Other Income, Net [Abstract] |  |  |  |
Investment and other income, net increase (decrease) | $ 38 | $ 13 | $ (25) | $ 22
OPEB remeasurement gain (loss) | 0 | 18 | (8) | 27
Pension benefit reduction |  |  | 9 |
Pension remeasurement gain (loss) | $ 44 | $ (72) | 44 | $ 2
Combined increase in pension benefit and OPEB costs accruals |  |  | 35 |
Increase in pension remeasurement gain |  |  | $ 42 |

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- Definition Combined Pension Benefit And OPEB Costs Accruals, Increase Decrease + References No definition available. + Details
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- Definition Investment And Other Nonoperating Income Expense Net Increase Decrease + References No definition available. + Details
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- Definition Pension Benefit Reduction + 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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