Compensation and Benefit Plans (Expense Components) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012		Jun. 30, 2013		Jun. 30, 2012
Postretirement Benefits Other Than Pensions
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	$ 14		$ 12		$ 28		$ 24
Interest cost	26		29		52		57
Expected return on plan assets	(30)		(27)		(60)		(54)
Special termination benefits	10	[1]	0	[1]	10	[1]	0	[1]
Amortization of prior service cost	(9)		(9)		(18)		(18)
Amortization of net loss	7	[2]	11	[2]	14	[2]	23	[2]
Expense under accounting standards	18		16		26		32
Pension Plans
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	38		39		76		77
Interest cost	42		45		84		91
Expected return on plan assets	(57)		(55)		(114)		(111)
Settlement costs	49		0		49		0
Amortization of prior service cost	1		1		2		2
Amortization of net loss	15	[3]	16	[3]	30	[3]	33	[3]
Expense under accounting standards	88		46		127		92
Regulatory adjustment (deferred)	(31)		27		(14)		54
Total expense recognized	57		73		113		146
Net loss reclassified	4				7
Southern California Edison | Postretirement Benefits Other Than Pensions
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	14		12		27		24
Interest cost	26		28		52		56
Expected return on plan assets	(30)		(27)		(60)		(54)
Special termination benefits	10	[1]	0	[1]	10	[1]	0	[1]
Amortization of prior service cost	(9)		(9)		(18)		(18)
Amortization of net loss	7	[2]	11	[2]	14	[2]	22	[2]
Expense under accounting standards	18		15		25		30
Net loss reclassified	0				0
Southern California Edison | Pension Plans
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	37		37		74		74
Interest cost	41		45		82		90
Expected return on plan assets	(57)		(55)		(114)		(110)
Settlement costs	48		0		48		0
Amortization of prior service cost	1		1		2		2
Amortization of net loss	14	[3]	15	[3]	28	[3]	30	[3]
Expense under accounting standards	84		43		120		86
Regulatory adjustment (deferred)	(31)		27		(14)		54
Total expense recognized	53		70		106		140
Net loss reclassified	3				5
Maximum | Postretirement Benefits Other Than Pensions
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Net loss reclassified	$ 1				$ 1

[1] Due to the reduction in workforce, SCE has incurred costs for extended retiree health care coverage.

[2] Includes the amount of net loss reclassified from other comprehensive loss. The amount reclassified for Edison International and SCE was less than $1 million and zero for the three- and six-months ended June 30, 2013, respectively.

[3] Includes the amount of net loss reclassified from other comprehensive loss. The amount reclassified for Edison International and SCE was $4 million and $3 million for the three months ended June 30, 2013, respectively, and $7 million and $5 million for the six months ended June 30, 2013, respectively.