Income Taxes (Reconciliation of Unrecognized Tax Benefits) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Reconciliation of Unrecognized Tax Benefits
Beginning balance	$ 812	$ 631	$ 565
Tax positions taken during the current year, Increases	19	33	39
Tax positions taken during a prior year, Increases	43	177	102
Tax positions taken during a prior year, Decreases	(109)	(11)	(75)
Tax positions taken during a prior year: Increases (decreases) - deconsolidation of EME	50	(18)	0
Decreases for settlements during the period	0	0	0
Ending balance	815	812	631
Southern California Edison
Reconciliation of Unrecognized Tax Benefits
Beginning balance	571	373	329
Tax positions taken during the current year, Increases	22	35	34
Tax positions taken during a prior year, Increases	45	169	82
Tax positions taken during a prior year, Decreases	(106)	(6)	(72)
Tax positions taken during a prior year: Increases (decreases) - deconsolidation of EME	0	0	0
Decreases for settlements during the period	0	0	0
Ending balance	$ 532	$ 571	$ 373