Nuclear Decommissioning Fund (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024		Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale, Unrealized Gain	$ 1,400		$ 1,200
Debt Securities, Available-for-Sale, Unrealized Loss	49		29
Equity investments in unconsolidated subsidiaries	246		244
Miscellaneous investments	156		144
Final Contractual Maturity [Abstract]
Due in 1 Year or Less	7
Due in 1 to 5 Years	308
Due in 5 to 10 Years	269
Due after 10 Years	262
Total	846
Fair Value Measured on a Recurring Basis | Cost
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Decommissioning fund investments	2,130	[1]	2,054	[2]
Fair Value Measured on a Recurring Basis | Cost | Cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	39	[1]	41	[2]
Fair Value Measured on a Recurring Basis | Cost | Commingled Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	703	[1]	721	[2]
Fair Value Measured on a Recurring Basis | Cost | Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	866	[1]	784	[2]
Fair Value Measured on a Recurring Basis | Cost | Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	522	[1]	508	[2]
Fair Value Measured on a Recurring Basis | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Alternative Investment	1,025	[1]	1,049	[2]
Decommissioning fund investments	3,494	[1]	3,211	[2]
Final Contractual Maturity [Abstract]
Total	96		88
Fair Value Measured on a Recurring Basis | Fair Value | Cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	39	[1]	41	[2]
Alternative Investment	0	[1]	0	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Commingled Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Alternative Investment	1,025	[1]	1,049	[2]
Investments, Fair Value Disclosure	1,025	[1]	1,049	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Alternative Investment	0	[1]	0	[2]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	846	[1]	780	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Alternative Investment	0	[1]	0	[2]
Equity Securities, FV-NI, Current	1,584	[1]	1,341	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Decommissioning fund investments	1,622	[1]	1,380	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Level 1 | Cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	39	[1]	41	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Level 1 | Commingled Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	0	[1]	0	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Level 1 | Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	0	[1]	0	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Level 1 | Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	1,583	[1]	1,339	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Decommissioning fund investments	833	[1]	773	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Level 2 | Cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	0	[1]	0	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Level 2 | Commingled Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	0	[1]	0	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Level 2 | Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	832	[1]	771	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Level 2 | Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	1	[1]	2	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Decommissioning fund investments	14	[1]	9	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Level 3 | Cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	0	[1]	0	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Level 3 | Commingled Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	0	[1]	0	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Level 3 | Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	14	[1]	9	[2]
Fair Value Measured on a Recurring Basis | Fair Value | Level 3 | Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	$ 0	[1]	$ 0	[2]

[1] Reported in nuclear decommissioning fund and other investments on the consolidated balance sheets, which also includes $246 million of equity method investments and $156 million of rabbi trust assets and other miscellaneous investments.

[2] Reported in nuclear decommissioning fund and other investments on the consolidated balance sheets, which also includes $244 million of equity investments in unconsolidated subsidiaries and $144 million of rabbi trust assets and other miscellaneous investments.