Income Taxes (Tax Rate Reconciliation) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Effective Tax Rate
Income from continuing operations before income taxes	$ 333	$ 424
Provision for income tax at federal statutory rate of 35%	117	148
State tax, net of federal benefit	6	11
Property-related	(79)	(60)
Change related to uncertain tax positions	(1)	15
Other	(5)	(8)
Total income tax expense from continuing operations	$ 38	$ 106
Effective tax rate	11.40%	25.00%
Federal statutory rate	35.00%
Southern California Edison
Effective Tax Rate
Income from continuing operations before income taxes	$ 367	$ 440
Provision for income tax at federal statutory rate of 35%	128	154
State tax, net of federal benefit	9	14
Property-related	(79)	(60)
Change related to uncertain tax positions	(1)	10
Other	(7)	(11)
Total income tax expense from continuing operations	$ 50	$ 107
Effective tax rate	13.60%	24.30%
Federal statutory rate	35.00%