Derivative Instruments (Balance Sheet Disclosures) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014		Dec. 31, 2013
Fair Value of Derivative Instruments
Short-Term, Derivative Assets	$ 103		$ 122
Long-Term, Derivative Assets	245		251
Short-Term, Derivative Liabilities	154		152
Long-Term, Derivative Liabilities	947		1,042
Southern California Edison
Fair Value of Derivative Instruments
Short-Term, Derivative Assets	103		122
Long-Term, Derivative Assets	245		251
Short-Term, Derivative Liabilities	154		152
Long-Term, Derivative Liabilities	947		1,042
Southern California Edison | Electric Utility | Economic hedges
Derivatives
Collateral Already Posted, Aggregate Fair Value	0
Southern California Edison | Commodity Contracts | Electric Utility
Fair Value of Derivative Instruments
Short-Term, Derivative Assets	103		122
Long-Term, Derivative Assets	245		251
Derivative Assets, Total	348		373
Short-Term, Derivative Liabilities	154		152
Long-Term, Derivative Liabilities	947		1,042
Derivative Liabilities, Total	1,101		1,194
Net Liability	753		821
Southern California Edison | Commodity Contracts | Electric Utility | Economic hedges
Fair Value of Derivative Instruments
Short-Term, Derivative Assets	103		141
Long-Term, Derivative Assets	245		251
Derivative Assets, Total	348		392
Short-Term, Derivative Liabilities	159		178
Long-Term, Derivative Liabilities	948		1,045
Derivative Liabilities, Total	1,107		1,223
Net Liability	759		831
Southern California Edison | Commodity Contracts | Electric Utility | Netting and Collateral
Fair Value of Derivative Instruments
Short-Term, Derivative Assets			(19)
Long-Term, Derivative Assets			0
Derivative Assets, Total			(19)
Short-Term, Derivative Liabilities			(19)
Long-Term, Derivative Liabilities			0
Derivative Liabilities, Total			(19)
Net Liability			0
Southern California Edison | Commodity Contracts | Electric Utility | Cash Collateral Posted
Fair Value of Derivative Instruments
Short-Term, Derivative Assets	0	[1]	0	[1]
Long-Term, Derivative Assets	0	[1]	0	[1]
Derivative Assets, Total	0	[1]	0	[1]
Short-Term, Derivative Liabilities	(5)	[1]	(7)	[1]
Long-Term, Derivative Liabilities	(1)	[1]	(3)	[1]
Derivative Liabilities, Total	(6)	[1]	(10)	[1]
Net Liability	(6)	[1]	(10)	[1]
Other Current Assets | Southern California Edison | Commodity Contracts
Derivatives
Collateral Already Posted, Aggregate Fair Value	$ 6		$ 19

[1] In addition, at September 30, 2014 and December 31, 2013, SCE had posted $6 million and $19 million, respectively, of collateral that is not offset against derivative liabilities and is reflected in "Other current assets" on the consolidated balance sheets.