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Investment And Other Income, Net (Components Of Investment And Other Income) (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] |  |  |  |
Interest and dividend income | $ 4 | $ 20 | $ 20 | $ 58
Pension benefit | 7 | 9 | 19 | 30
OPEB costs | (1) | (1) | (3) | (3)
OPEB remeasurement gain (loss) | 0 | (21) | (8) | 6
Pension remeasurement gain | 0 | 23 | 44 | 25
Pension building sale (loss) | (19) |  | (19) |
All other, net |  | (1) | 1 | 1
Total investment and other income (loss), net | $ (9) | $ 29 | $ 54 | $ 117

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