Nuclear Decommissioning Trust Funds - Schedule of Unrealized Gain (Loss) on Nuclear Decommissioning Trust Funds (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Cash equivalents, Amortized Cost	$ 632	$ 400
Cash equivalents, Fair Value	13	9
Equity securities, Amortized Cost	498	491
Equity securities, Unrealized Gains	636	575
Equity securities, Unrealized Losses	56	53
Equity securities, Fair Value	1,078	1,013
Debt securities, Amortized Cost	600	570
Debt securities, Unrealized Gains	3	10
Debt securities, Unrealized Losses	5	1
Debt securities	598	579
Receivables (payables), net, Amortized Cost	(30)	(26)
Receivables (payables), net, Fair Value	(30)	(26)
Amortized Cost	1,081	1,044
Unrealized Gains	639	585
Unrealized Losses	61	54
NDT funds	1,659	1,575
Cash equivalents
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Cash equivalents, Amortized Cost	13	9
Cash equivalents, Fair Value	$ 13	$ 9

Decommissioning Fund Investments, Accumulated Gross Unrealized Gain, Before Tax

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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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