Asset Retirement Obligations - Non-Nuclear Asset Retirement Obligations Rollforward (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Accretion expense	$ 543	$ 514	$ 500
Nonnuclear Decommissioning Asset Retirement Obligation
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	216	212
Other one-time charges	18	5
Accretion expense	11	11
Asset divestitures	(1)	(19)
Payments	(5)	(3)
Ending balance	$ 239	216	$ 212
Nonnuclear Decommissioning Asset Retirement Obligation \| Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Other one-time charges		$ 10

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 25
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=116646717&loc=d3e6290-110844

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI https://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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Amount of cash paid during the period to settle an asset retirement obligation. Amounts paid to settle an asset retirement obligation are generally included in the operating section of the Statement of Cash Flows.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 17
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3367-108585

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 45
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=6392676&loc=SL5974666-110848

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Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(2)
-URI https://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(4)
-URI https://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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