Trust Investments (Proceeds From The Sales Of And The Net Realized Gains On Securities in the NDT and Rabbi Trusts) (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Schedule of Trust Investments [Line Items]
Proceeds from Sale of Trust Investments		$ 369	$ 402
Net Gains (Losses) on Trust Investments		95	46
Nuclear Decommissioning Trust (NDT) Fund [Member]
Schedule of Trust Investments [Line Items]
Proceeds from Sale of Trust Investments	[1]	360	396
Gross Realized Gains		31	21
Gross Realized Losses		(14)	(27)
Net Realized Gains (Losses)	[2]	17	(6)
Unrealized Gain (Loss) on Equity Securities		78	51
Net Gains (Losses) on Trust Investments		95	45
Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
Proceeds from Sale of Trust Investments		9	6
Gross Realized Gains		1	1
Gross Realized Losses		(1)	(1)
Net Realized Gains (Losses)	[3]	0	0
Unrealized Gain (Loss) on Equity Securities		0	1
Net Gains (Losses) on Trust Investments		$ 0	$ 1

[1] Includes activity in accounts related to the liquidation of funds being transitioned within the trust.

[2] The cost of these securities was determined on the basis of specific identification.

[3] The cost of these securities was determined on the basis of specific identification.