Properties - Gain (Loss) on Sale of Property Rights (Details) - USD ($) $ in Millions	12 Months Ended	21 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Gains	$ 34	$ 238	$ 454
Proceeds and Advances from Property Dispositions	52	246	529
Virginia Line Segments
Property, Plant and Equipment [Line Items]
Gains	0	144	349	$ 493
Proceeds and Advances from Property Dispositions	$ 0	$ 125	$ 400	$ 525

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

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- Definition

The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 12
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-12

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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.

+ References

No definition available.

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