Income Taxes (Tax Rate Reconciliation) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Line Items]
Income from continuing operations before income taxes	$ 1,590	$ 1,568	$ 1,979
Provision for income tax at federal statutory rate of 35%	556	549	693
Increase in income tax from:
Regulatory asset write-off	0	382	0
State tax, net of federal benefit	29	5	56
Property-related	(362)	(341)	(252)
Change related to uncertain tax positions	(4)	(67)	5
San Onofre OII settlement	0	0	(23)
Share-based compensation	(28)	0	0
Other	(14)	(42)	(36)
Total continuing operations	$ 177	$ 486	$ 443
Effective tax rate	11.10%	31.00%	22.40%
Federal statutory rate	35.00%	35.00%	35.00%
State
Increase in income tax from:
Share-based compensation	$ (4)
SCE
Income Tax Disclosure [Line Items]
Income from continuing operations before income taxes	1,755	$ 1,618	$ 2,039
Provision for income tax at federal statutory rate of 35%	614	566	714
Increase in income tax from:
Regulatory asset write-off	0	382	0
State tax, net of federal benefit	43	34	55
Property-related	(362)	(341)	(252)
Change related to uncertain tax positions	(8)	(94)	12
San Onofre OII settlement	0	0	(23)
Share-based compensation	(13)	0	0
Other	(18)	(40)	(32)
Total continuing operations	$ 256	$ 507	$ 474
Effective tax rate	14.60%	31.30%	23.20%
SCE | State
Increase in income tax from:
Share-based compensation	$ (1)