Investment And Other Income, Net (Components Of Investment And Other Income) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Investment And Other Income, Net [Abstract]
Interest and dividend income	$ 9	$ 18
Pension benefit	6	12
OPEB costs	(1)	(1)
OPEB remeasurement gain (loss)	(8)	9
Pension remeasurement gain	44	74
All other, net	(1)
Total investment and other income, net	$ 49	$ 112

Amount of investment and other nonoperating income (expense), net.

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- Definition

OPEB Costs (Benefit)

+ References

No definition available.

+ Details

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- Definition

OPEB Remeasurement

+ References

No definition available.

+ Details

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- Definition

Pension Remeasurement Gain (Loss)

+ References

No definition available.

+ Details

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- Definition

Amount of operating dividend and interest income, including amortization and accretion of premiums and discounts, on securities.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 946
-SubTopic 320
-Name Accounting Standards Codification
-Section S99
-Paragraph 6
-Subparagraph (SX 210.12-14(Column E)(Footnote 4))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477271/946-320-S99-6

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- Definition

Amount of income (expense) related to nonoperating activities, classified as other.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(9))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

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- References

No definition available.

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- Definition

Amount of cost (reversal of cost) for pension and other postretirement benefits.

+ References

No definition available.

+ Details

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