Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Pension and PBOP – net loss:
Other	$ 0	$ (1)	$ 0	$ (1)
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(53)	(56)	(56)	(58)
Pension and PBOP – net loss:
Ending Balance	(51)	(55)	(51)	(55)
Accumulated Other Comprehensive Loss | Southern California Edison
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(20)	(26)	(22)	(28)
Pension and PBOP – net loss:
Ending Balance	(19)	(25)	(19)	(25)
Accumulated Defined Benefit Plans Adjustment
Pension and PBOP – net loss:
Other comprehensive loss before reclassifications	0	0	0	(4)
Reclassified from accumulated other comprehensive loss	2	2	5	8
Other	0	(1)	0	(1)
Change	2	1	5	3
Accumulated Defined Benefit Plans Adjustment | Southern California Edison
Pension and PBOP – net loss:
Other comprehensive loss before reclassifications	0	0	0	(1)
Reclassified from accumulated other comprehensive loss	1	1	3	4
Change	$ 1	$ 1	$ 3	$ 3