Compensation and Benefit Plans (Supplemental Data on Stock-Based Compensation) (Details) (Employee Stock Option, USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value per option granted (dollars per share)	$ 5.40	$ 5.22	$ 5.61
Fair value of options vested	$ 17	$ 17	$ 18
Cash used to purchase shares to settle options	199	169	90
Cash from participants to exercise stock options	140	101	59
Value of options exercised	59	68	31
Tax benefits from options exercised	24	27	12
Southern California Edison
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value per option granted (dollars per share)	$ 5.38	$ 5.22	$ 5.61
Fair value of options vested	10	10	10
Cash used to purchase shares to settle options	130	96	46
Cash from participants to exercise stock options	92	59	28
Value of options exercised	38	37	18
Tax benefits from options exercised	$ 15	$ 15	$ 7