Other Investments (Textual) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other Investments [Line Items]
Proceeds from sale of securities	$ 10,079,000,000	$ 5,617,000,000	$ 2,122,000,000
Southern California Edison
Other Investments [Line Items]
Contributions received for decommissioning trusts	5,000,000	22,000,000	23,000,000
Period of reviewing contributions from decommissioning trusts (in years)	3 years
Proceeds from sale of securities	10,079,000,000	5,617,000,000	2,122,000,000
Unrealized holding gains, net of losses	1,800,000,000	1,700,000,000
Decommissioning Trust, Deferred Income Taxes	441,000,000
Decommissioning Fund Investments, Fair Value, Net of Deferred Income Tax	$ 4,400,000,000