Supplementary Financial Information - Schedule of Investments (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Supplementary Financial Information [Abstract]
Nuclear decommissioning trusts	$ 4,930	$ 4,440
Assets related to employee benefit plans	13	14
Land investments	42	42
Other investments	23	16
Total investments	$ 5,008	$ 4,512

Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant