Other Investments (Summary of Changes in Fair Value of the Nuclear Decommissioning Trusts) (Details) (USD $) In Millions, unless otherwise specified			3 Months Ended		6 Months Ended
	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014 Southern California Edison	Jun. 30, 2013 Southern California Edison	Jun. 30, 2014 Southern California Edison	Jun. 30, 2013 Southern California Edison
Summary Of Changes In The Fair Value [Roll Forward]
Balance at beginning of period	$ 4,740	$ 4,494	$ 4,587	$ 4,246	$ 4,494	$ 4,048
Gross realized gains			28	137	38	142
Gross realized losses			0	(1)	0	(2)
Unrealized gains (losses), net			107	(185)	169	(9)
Other-than-temporary impairments			(3)	(21)	(6)	(29)
Interest, dividends, contributions and other			21	5	45	31
Balance at end of period	$ 4,740	$ 4,494	$ 4,740	$ 4,181	$ 4,740	$ 4,181