Consolidated Statements of Changes in Equity (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013		Sep. 30, 2012
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			$ 732		$ 1,664
Net Income (loss)	(448)	(162)	(614)		(348)
OCI, net of tax	0	(13)	29		(34)
Payments to EIX for stock purchases related to stock-based compensation			(13)		(14)
Cash Contribution From Parent			6	[1]
NonCash Contribution From Parent			32	[1]	0	[2]
Excess tax benefits related to stock option exercises			2		3
Other stock transactions, net			2		4
Contributions from noncontrolling interests			94	[3]	242	[3]
Distributions to Noncontrolling Interests			(11)		(14)
Transfers of assets to Capistrano Wind Partners					(21)	[4]
Balance	259	1,482	259		1,482
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			64		64
Net Income (loss)			0		0
OCI, net of tax			0		0
Payments to EIX for stock purchases related to stock-based compensation			0		0
Cash Contribution From Parent			0	[1]
NonCash Contribution From Parent			0
Excess tax benefits related to stock option exercises			0		0
Other stock transactions, net			0		0
Contributions from noncontrolling interests			0	[3]	0	[3]
Distributions to Noncontrolling Interests			0		0
Transfers of assets to Capistrano Wind Partners					0	[4]
Balance	64	64	64		64
Additional Paid-in Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			1,095		1,327
Net Income (loss)			0		0
OCI, net of tax			0		0
Payments to EIX for stock purchases related to stock-based compensation			0		0
Cash Contribution From Parent			6	[1]
NonCash Contribution From Parent			32	[1]
Excess tax benefits related to stock option exercises			2		3
Other stock transactions, net			2		4
Contributions from noncontrolling interests			0	[3]	0	[3]
Distributions to Noncontrolling Interests			0		0
Transfers of assets to Capistrano Wind Partners					(21)	[4]
Balance	1,137	1,313	1,137		1,313
Retained Earnings (Deficit)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			(577)		365
Net Income (loss)			(635)		(360)
OCI, net of tax			0		0
Payments to EIX for stock purchases related to stock-based compensation			(13)		(14)
Cash Contribution From Parent			0	[1]
NonCash Contribution From Parent			0
Excess tax benefits related to stock option exercises			0		0
Other stock transactions, net			0		0
Contributions from noncontrolling interests			0	[3]	0	[3]
Distributions to Noncontrolling Interests			0		0
Transfers of assets to Capistrano Wind Partners					0	[4]
Balance	(1,225)	(9)	(1,225)		(9)
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			(138)		(94)
Net Income (loss)			0		0
OCI, net of tax			29		(34)
Payments to EIX for stock purchases related to stock-based compensation			0		0
Cash Contribution From Parent			0	[1]
NonCash Contribution From Parent			0
Excess tax benefits related to stock option exercises			0		0
Other stock transactions, net			0		0
Contributions from noncontrolling interests			0	[3]	0	[3]
Distributions to Noncontrolling Interests			0		0
Transfers of assets to Capistrano Wind Partners					0	[4]
Balance	(109)	(128)	(109)		(128)
Non-controlling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			288		2
Net Income (loss)			21		12
OCI, net of tax			0		0
Payments to EIX for stock purchases related to stock-based compensation			0		0
Cash Contribution From Parent			0	[1]
NonCash Contribution From Parent			0
Excess tax benefits related to stock option exercises			0		0
Other stock transactions, net			0		0
Contributions from noncontrolling interests			94	[3]	242	[3]
Distributions to Noncontrolling Interests			(11)		(14)
Transfers of assets to Capistrano Wind Partners					0	[4]
Balance	$ 392	$ 242	$ 392		$ 242

[1] During 2013, EME received contributions from EIX related to the tax-allocation agreements. For further information, see Note 7—Income Taxes—EME—Effective Tax Rate.

[2] During 2013, the non-cash contribution from EIX relates to the tax-allocation agreements. For further information, see Note 7—Income Taxes—EME—Effective Tax Rate.

[3] Funds contributed by third-party investors to Capistrano Wind Partners. For further information, see Note 3—Variable Interest Entities—Projects or Entities that are Consolidated—Capistrano Wind Partners.

[4] Additional paid in capital was reduced by $21 million due to a new tax basis in the assets transferred to Capistrano Wind Partners.