Nuclear Decommissioning Trust Funds - Summary of Maturities for Available-for-sale Debt Securities (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Maturities within one year	$ 75	$ 105
Maturities within two to five years	177	194
Maturities thereafter	346	280
Debt securities, fair value	$ 598	$ 579

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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