Nuclear Decommissioning Trust Fund - Summary of Aggregate Fair Values and Realized Gains and Losses (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Nuclear decommissioning trust fund disclosure
Fair Value	$ 838	$ 1,008
Unrealized Gains	346	471
Unrealized Losses	36	2
Cash and cash equivalents
Nuclear decommissioning trust fund disclosure
Fair Value	15	33
Unrealized Gains	0	0
Unrealized Losses	0	0
U.S. government and federal agency obligations
Nuclear decommissioning trust fund disclosure
Fair Value	86	112
Unrealized Gains	0	5
Unrealized Losses	$ 5	$ 1
Weighted- average maturities (in years)	11 years	10 years
Federal agency mortgage-backed securities
Nuclear decommissioning trust fund disclosure
Fair Value	$ 101	$ 100
Unrealized Gains	0	2
Unrealized Losses	$ 11	$ 0
Weighted- average maturities (in years)	26 years	25 years
Commercial mortgage-backed securities
Nuclear decommissioning trust fund disclosure
Fair Value	$ 35	$ 44
Unrealized Gains	0	1
Unrealized Losses	$ 4	$ 0
Weighted- average maturities (in years)	30 years	27 years
Corporate debt securities
Nuclear decommissioning trust fund disclosure
Fair Value	$ 114	$ 122
Unrealized Gains	0	7
Unrealized Losses	$ 13	$ 1
Weighted- average maturities (in years)	12 years	14 years
Equity securities
Nuclear decommissioning trust fund disclosure
Fair Value	$ 486	$ 593
Unrealized Gains	346	456
Unrealized Losses	3	0
Foreign government fixed income securities
Nuclear decommissioning trust fund disclosure
Fair Value	1	4
Unrealized Gains	0	0
Unrealized Losses	$ 0	$ 0
Weighted- average maturities (in years)	17 years	13 years
South Texas Project
Nuclear decommissioning trust fund disclosure
Ownership Interest (as a percent)	44.00%

Decommissioning Fund Investments, Unrealized Gains

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Decommissioning Fund Investments, Unrealized Loss

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The weighted-average maturity period for securities of nuclear decommissioning trust funds assets.

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The fair value of investments held in a trust fund to pay for the costs of decontaminating and decommissioning facilities, whether such amount is presented as a separate caption or as a parenthetical disclosure on the balance sheet. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
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The proportionate share of interest (percent) in a jointly owned utility plant.

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-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 10.C)
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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.

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