Compensation and Benefit Plans (Stock Option Activity) (Details) (Employee Stock Option, USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014
Exercise Price
Beginning balance, weighted average exercise price (dollars per share)	$ 40.22
Granted, weighted average exercise price (dollars per share)	$ 52.67
Expired, weighted average exercise price (dollars per share)	$ 49.95
Forfeited, weighted average exercise price (dollars per share)	$ 46.20
Exercised, weighted average exercise price (dollars per share)	$ 38.03
Ending balance, weighted average exercise price (dollars per share)	$ 42.84
Vested and expected to vest, weighted average exercise price (dollars per share)	$ 42.68
Exercisable, weighted average exercise price (dollars per share)	$ 39.43
Stock options
Beginning balance (number of options)	17,226,845
Grants (number of options)	2,070,819
Expired (number of options)	(20,841)
Forfeited (number of options)	(278,134)
Exercised (number of options)	(5,379,954)
Ending balance (number of options)	13,618,735
Vested and expected to vest (number of options)	13,216,820
Exercisable (number of options)	7,989,189
Remaining Contractual Term (Years)
Outstanding at December 31, 2014	5 years 9 months 22 days
Vested and expected to vest at December 31, 2014	5 years 9 months
Exercisable at December 31, 2014	4 years 3 months 26 days
Aggregate Intrinsic Value (in millions)
Vested and expected to vest at December 31, 2014	$ 301
Exercisable at December 31, 2014	208
Southern California Edison
Exercise Price
Beginning balance, weighted average exercise price (dollars per share)	$ 40.28
Granted, weighted average exercise price (dollars per share)	$ 53.21
Expired, weighted average exercise price (dollars per share)	$ 49.95
Forfeited, weighted average exercise price (dollars per share)	$ 47.27
Exercised, weighted average exercise price (dollars per share)	$ 38.54
Transfers, net, weighted average exercise price (dollars per share)	$ 37.95
Ending balance, weighted average exercise price (dollars per share)	$ 43.82
Vested and expected to vest, weighted average exercise price (dollars per share)	$ 43.63
Exercisable, weighted average exercise price (dollars per share)	$ 39.61
Stock options
Beginning balance (number of options)	9,045,998
Grants (number of options)	1,194,281
Expired (number of options)	(20,841)
Forfeited (number of options)	(205,286)
Exercised (number of options)	(3,210,425)
Transfers, net (number of options)	(801,567)
Ending balance (number of options)	6,002,160
Vested and expected to vest (number of options)	5,762,299
Exercisable (number of options)	2,997,941
Remaining Contractual Term (Years)
Outstanding at December 31, 2014	6 years 3 months 15 days
Vested and expected to vest at December 31, 2014	6 years 2 months 19 days
Exercisable at December 31, 2014	4 years 7 months 17 days
Aggregate Intrinsic Value (in millions)
Vested and expected to vest at December 31, 2014	126
Exercisable at December 31, 2014	$ 78