Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
AOCI Attributable to Parent, Net of Tax
Beginning balance	$ 17,944	$ 17,522
Changes in accumulated other comprehensive loss
Other comprehensive income, net of tax		2
Ending Balance	17,615	17,549
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax
Beginning balance	(9)	(11)
Changes in accumulated other comprehensive loss
Other comprehensive income, net of tax		2
Ending Balance	(9)	(9)
Foreign currency translation adjustments
Changes in accumulated other comprehensive loss
Other comprehensive (loss) income before reclassifications		2
SCE
AOCI Attributable to Parent, Net of Tax
Beginning balance	21,404	20,789
Changes in accumulated other comprehensive loss
Other comprehensive income, net of tax	1
Ending Balance	21,097	20,807
SCE | Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax
Beginning balance	(12)	(8)
Changes in accumulated other comprehensive loss
Other comprehensive income, net of tax	1
Ending Balance	(11)	$ (8)
SCE | Accumulated Defined Benefit Plans Adjustment
Changes in accumulated other comprehensive loss
Reclassified from accumulated other comprehensive loss1	$ 1