Nuclear Decommissioning Trust Funds - Schedule of Unrealized Gain (Loss) on Nuclear Decommissioning Trust Funds (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Cash equivalents, Amortized Cost	$ 648	$ 400
Cash equivalents, Fair Value	8	9
Equity securities, Amortized Cost	504	491
Equity securities, Unrealized Gains	672	575
Equity securities, Unrealized Losses	44	53
Equity securities, Fair Value	1,132	1,013
Debt securities, Amortized Cost	581	570
Debt securities, Unrealized Gains	12	10
Debt securities, Unrealized Losses	0	1
Debt securities	593	579
Receivables (payables), net, Amortized Cost	4	(26)
Receivables (payables), net, Fair Value	4	(26)
Amortized Cost	1,097	1,044
Unrealized Gains	684	585
Unrealized Losses	44	54
NDT funds	1,737	1,575
Cash equivalents
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Cash equivalents, Amortized Cost	8	9
Cash equivalents, Fair Value	$ 8	$ 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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