Business Segments (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012		Mar. 31, 2011		Dec. 31, 2011
Segment Reporting Information
Operating Revenue:	$ 2,856		$ 2,782
Net Income (Loss) attributable to Edison International:	93		200
Total Assets:	49,384				48,039
Income (loss) from discontinued operations, net of tax	(1)		(2)
Electric Utility
Segment Reporting Information
Operating Revenue:	2,412		2,232
Net Income (Loss) attributable to Edison International:	182		222
Total Assets:	41,605				40,315
Competitive Power Generation
Segment Reporting Information
Operating Revenue:	444		552
Net Income (Loss) attributable to Edison International:	(84)	[1]	(20)	[1]
Total Assets:	8,472				8,392
Parent and Other
Segment Reporting Information
Operating Revenue:	0	[2]	(2)	[2]
Net Income (Loss) attributable to Edison International:	(5)	[2]	(2)	[2]
Total Assets:	$ (693)	[2]			$ (668)	[2]

[1] Includes losses from discontinued operations of $(1) million and $(2) million for the three months ended March 31, 2012 and 2011, respectively.

[2] Includes amounts from Edison International (parent) and other Edison International subsidiaries that are not significant as a reportable segment, as well as intercompany eliminations.