Property, Plant and Equipment (Schedule of Property, Plant and Equipment) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Accumulated depreciation	$ (9,566)	$ (9,355)
Total utility property, plant and equipment	41,269	38,708
SCE
Property, Plant and Equipment [Line Items]
Distribution	25,026	23,633
Transmission	13,800	13,127
Generation	3,598	3,468
General plant and other	4,398	4,534
Accumulated depreciation	(9,566)	(9,355)
Total utility property, plant and equipment, Gross	37,256	35,407
Construction work in progress	3,883	3,175
Nuclear fuel, at amortized cost	130	126
Total utility property, plant and equipment	$ 41,269	$ 38,708