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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, 2023	Nov. 01, 2023
Nuclear decommissioning trust fund disclosure
Fair Value	$ 838	$ 0
Unrealized Gains	346
Unrealized Losses	36
Cash and cash equivalents
Nuclear decommissioning trust fund disclosure
Fair Value	15
Unrealized Gains	0
Unrealized Losses	0
U.S. government and federal agency obligations
Nuclear decommissioning trust fund disclosure
Fair Value	86
Unrealized Gains	0
Unrealized Losses	$ 5
Weighted- average maturities (in years)	11 years
Federal agency mortgage-backed securities
Nuclear decommissioning trust fund disclosure
Fair Value	$ 101
Unrealized Gains	0
Unrealized Losses	$ 11
Weighted- average maturities (in years)	26 years
Commercial mortgage-backed securities
Nuclear decommissioning trust fund disclosure
Fair Value	$ 35
Unrealized Gains	0
Unrealized Losses	$ 4
Weighted- average maturities (in years)	30 years
Corporate debt securities
Nuclear decommissioning trust fund disclosure
Fair Value	$ 114
Unrealized Gains	0
Unrealized Losses	$ 13
Weighted- average maturities (in years)	12 years
Equity securities
Nuclear decommissioning trust fund disclosure
Fair Value	$ 486
Unrealized Gains	346
Unrealized Losses	3
Foreign government fixed income securities
Nuclear decommissioning trust fund disclosure
Fair Value	1
Unrealized Gains	0
Unrealized Losses	$ 0
Weighted- average maturities (in years)	17 years
South Texas Project
Nuclear decommissioning trust fund disclosure
Ownership Interest (as a percent)			44.00%

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Decommissioning Fund Investments, Unrealized Gains

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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.

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The proportionate share of interest (percent) in a jointly owned utility plant.

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