Property, Plant and Equipment (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Public Utilities, Property, Plant and Equipment, Plant in Service [Abstract]
Accumulated depreciation	$ (7,493)	$ (7,424)
Total utility property, plant and equipment	30,379	30,200
Southern California Edison
Public Utilities, Property, Plant and Equipment, Plant in Service [Abstract]
Transmission	9,117	7,059
Distribution	17,874	16,872
Generation	2,856	4,455
General plant and other	4,674	4,358
Accumulated depreciation	(7,493)	(7,424)
Total utility property, plant and equipment, Gross	27,028	25,320
Construction work in progress	3,219	4,271
Nuclear fuel, at amortized cost	132	609
Total utility property, plant and equipment	30,379	30,200
Southern California Edison | Eldorado
Public Utilities, Property, Plant and Equipment, Plant in Service [Abstract]
Construction work in progress	10
Nuclear fuel, at amortized cost	0
Plant in Service	87
Accumulated Depreciation	15
Net Book Value	82
Ownership Interest	62.00%
Southern California Edison | Pacific Intertie
Public Utilities, Property, Plant and Equipment, Plant in Service [Abstract]
Construction work in progress	7
Nuclear fuel, at amortized cost	0
Plant in Service	189
Accumulated Depreciation	74
Net Book Value	122
Ownership Interest	50.00%
Southern California Edison | Palo Verde (nuclear)
Public Utilities, Property, Plant and Equipment, Plant in Service [Abstract]
Construction work in progress	77
Nuclear fuel, at amortized cost	132
Plant in Service	1,842
Accumulated Depreciation	1,505
Net Book Value	546
Ownership Interest	16.00%
Southern California Edison | Aggregate Jointly Owned Utility Projects
Public Utilities, Property, Plant and Equipment, Plant in Service [Abstract]
Construction work in progress	94
Nuclear fuel, at amortized cost	132
Plant in Service	2,118
Accumulated Depreciation	1,594
Net Book Value	$ 750