Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Pension and PBOP – net loss:
Other	$ 0	$ 0	$ 2	$ 0
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(49)	(54)	(53)	(56)
Pension and PBOP – net loss:
Ending Balance	(48)	(53)	(48)	(53)
Accumulated Other Comprehensive Loss | Southern California Edison
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(18)	(21)	(20)	(22)
Pension and PBOP – net loss:
Ending Balance	(18)	(20)	(18)	(20)
Accumulated Defined Benefit Plans Adjustment
Pension and PBOP – net loss:
Reclassified from accumulated other comprehensive loss	1	1	3	3
Other	0	0	2	0
Change	1	1	5	3
Accumulated Defined Benefit Plans Adjustment | Southern California Edison
Pension and PBOP – net loss:
Reclassified from accumulated other comprehensive loss	1	1	2	2
Other	(1)	0	0	0
Change	$ 0	$ 1	$ 2	$ 2