Other Investments (Textual) (Details) $ in Millions		12 Months Ended
	Dec. 31, 2015 USD ($)	Dec. 31, 2015 USD ($) companies	Dec. 31, 2014 USD ($)
Southern California Edison
Other Investments [Line Items]
Repurchase agreements payable	$ 81	$ 81	$ 164
Unrealized holding gains, net of losses	1,400	1,400	$ 1,800
Deferred income taxes related to unrealized gains	360	360
Fair value, net of tax, in decommissioning trust fund	4,000	4,000
Reimbursed expenses from decommissioning trust fund		$ 471
Series of Individually Immaterial Business Acquisitions
Other Investments [Line Items]
Businesses acquired | companies		3
Aggregate purchase price	100
Maximum amount of contingent consideration	50	$ 50
Contingent consideration earn out period		4 years
Goodwill and identifiable intangibles acquired	$ 90	$ 90