Variable Interest Entities (Details) (USD $) In Millions, unless otherwise specified			1 Months Ended					3 Months Ended		6 Months Ended
	Jun. 30, 2011	Dec. 31, 2010	Apr. 30, 2011 EMG Wind Projects Variable Interest Entity, Primary Beneficiary	Jun. 30, 2011 EMG Wind Projects Variable Interest Entity, Primary Beneficiary mW	Dec. 31, 2010 EMG Wind Projects Variable Interest Entity, Primary Beneficiary mW	Jun. 30, 2011 Variable Interest Entity, Primary Beneficiary	Dec. 31, 2010 Variable Interest Entity, Primary Beneficiary	Jun. 30, 2011 Variable Interest Entity, Not Primary Beneficiary SCE Power Purchase Contracts mW	Jun. 30, 2010 Variable Interest Entity, Not Primary Beneficiary SCE Power Purchase Contracts	Jun. 30, 2011 Variable Interest Entity, Not Primary Beneficiary SCE Power Purchase Contracts mW	Jun. 30, 2010 Variable Interest Entity, Not Primary Beneficiary SCE Power Purchase Contracts
Details of projects or entities
Number of projects				13	14			16		16
Power generating capacity for majority interest (in megawatts)				570	580			3,820		3,820
Sale of ownership interest (as a percent)			75.00%
Number of projects consolidated				13	14
Summarized balance sheet information of VIEs
Current assets	$ 4,337	$ 4,422				$ 39	$ 26
Net property, plant and equipment	5,613	5,406				712	739
Other long-term assets	591	644				5	6
Total assets	47,075	45,530				756	771
Current liabilities	3,882	3,952				23	25
Long-term debt net of current portion	12,956	12,371				68	71
Deferred revenues						69	71
Other long-term liabilities	2,147	2,041				21	21
Total liabilities	35,318	34,036				181	188
Noncontrolling interests	1,031	911				3	4
Assets serving as collateral for the debt obligations						163	163
Power Purchase Agreement With Tolling Agreement								6		6
Power Purchase Agreement With Qualified Facilities								10		10
Payments to unconsolidated VIEs, power purchase contracts								$ 83	$ 117	$ 169	$ 242