SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF PARENT (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended												12 Months Ended
	Dec. 31, 2011		Sep. 30, 2011		Jun. 30, 2011		Mar. 31, 2011		Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011		Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Assets:
Cash and cash equivalents	$ 1,469								$ 1,389				$ 1,469		$ 1,389	$ 1,673
Other current assets	115								124				115		124
Total current assets	4,484								4,422				4,484		4,422
Investments in subsidiaries	525								559				525		559
Other	706								644				706		644
Total assets	48,039								45,530				48,039		45,530	41,444
Liabilities and Shareholders' Equity:
Accounts payable	1,419								1,362				1,419		1,362
Other current liabilities	1,049								998				1,049		998
Total current liabilities	4,348								3,952				4,348		3,952
Long-term debt	13,689								12,371				13,689		12,371
Common stockholders' equity	11,086								11,494				11,086		11,494	11,006	10,709
Total liabilities and equity	48,039								45,530				48,039		45,530
CONDENSED STATEMENTS OF INCOME
Operating revenue and other income	3,013		3,981		2,983		2,782		3,069	3,788	2,741	2,810	12,760		12,409	12,361
Operating expenses and interest expense													12,440		10,283	10,963
Loss before equity in earnings of subsidiaries	(1,319)		810		380		450		414	862	351	498	320		2,126	1,398
Equity in earnings (loss) of subsidiaries													86		106	42
Income (loss) before income taxes													(264)		1,657	854
Income tax benefit													(288)		354	(98)
Net income (loss) attributable to Edison International common shareholders													21		1,307	945
Weighted-average shares of common stock outstanding													326		326	326
Basic earnings (loss) per share (in dollars per share)	$ (2.57)		$ 1.31		$ 0.54		$ 0.61		$ 0.51	$ 1.56	$ 1.05	$ 0.72	$ (0.11)		$ 3.84	$ 2.59
Diluted earnings (loss) per share (in dollars per share)	$ (2.57)	[1]	$ 1.30	[1]	$ 0.54	[1]	$ 0.61	[1]	$ 0.51	$ 1.56	$ 1.05	$ 0.72	$ (0.11)	[1]	$ 3.82	$ 2.58
CONDENSED STATEMENTS OF CASH FLOWS
Net cash provided by operating activities													3,906		3,477	3,045
Cash flows from financing activities:
Long-term debt issued													1,376		1,936	939
Long-term debt issuance costs													(35)		(38)	(25)
Long-term debt repaid													(67)		(396)	(1,044)
Short-term debt financing - net													389		30	(2,058)
Settlements of stock-based compensation - net													(20)		(16)	(3)
Dividends paid													(417)		(411)	(404)
Net cash used by financing activities													1,107		1,053	(2,929)
Net cash provided by investing activities:													(4,933)		(4,814)	(2,359)
Net increase (decrease) in cash and cash equivalents													80		(284)	(2,243)
Cash and cash equivalents, beginning of year							1,389					1,673	1,389		1,673	3,916
Cash and cash equivalents, end of year	1,469								1,389				1,469		1,389	1,673
Short-term debt	429								115				429		115
Status of Credit Facility
Consolidated debt to total capitalization, ratio	0.65												0.65
Southern California Edison Company
Cash flows from financing activities:
Cash dividends received from consolidated subsidiaries													461		300
Minimum percentage of weighted-average common equity component authorization, set by CPUC (as a percent)													48.00%
Weighted-average common equity component authorization, set by CPUC remaining over number of months (in months)													13
Weighted-average common equity component of total capitalization (as a percent)													50.40%
Capacity to pay additional dividends													436
Weighted average interest rate (as a percent)	0.44%												0.44%
Status of Credit Facility
Commitment	2,894												2,894
Outstanding borrowings	(419)												(419)
Amount available	2,394												2,394
Edison International
Assets:
Cash and cash equivalents	28								21				28		21	18
Other current assets	236								285				236		285
Total current assets	264								306				264		306
Investments in subsidiaries	10,511								11,050				10,511		11,050
Deferred income tax	150								142				150		142
Other	192								67				192		67
Total assets	11,117								11,565				11,117		11,565
Liabilities and Shareholders' Equity:
Accounts payable	4								0				4		0
Other current liabilities	448								456				448		456
Total current liabilities	452								456				452		456
Long-term debt	400								410				400		410
Other	210								116				210		116
Common stockholders' equity	10,055								10,583				10,055		10,583
Total liabilities and equity	11,117								11,565				11,117		11,565
CONDENSED STATEMENTS OF INCOME
Operating revenue and other income													0		0	1
Operating expenses and interest expense													63		56	50
Loss before equity in earnings of subsidiaries													(63)		(56)	(49)
Equity in earnings (loss) of subsidiaries													(1)		1,262	833
Income (loss) before income taxes													(64)		1,206	784
Income tax benefit													(27)		(50)	(65)
Net income (loss) attributable to Edison International common shareholders													(37)		1,256	849
Weighted-average shares of common stock outstanding													326		326	326
Basic earnings (loss) per share (in dollars per share)													$ (0.11)		$ 3.84	$ 2.59
Diluted earnings (loss) per share (in dollars per share)													$ (0.11)		$ 3.82	$ 2.58
CONDENSED STATEMENTS OF CASH FLOWS
Net cash provided by operating activities													437		90	267
Cash flows from financing activities:
Long-term debt issued													0		399	9
Long-term debt issuance costs													0		(3)	0
Long-term debt repaid													0		0	(7)
Short-term debt financing - net													(9)		(66)	(165)
Settlements of stock-based compensation - net													(5)		(6)	(5)
Capital transfer													0		0	3
Dividends paid													(417)		(411)	(404)
Net cash used by financing activities													(431)		(87)	(569)
Net cash provided by investing activities:													1		0	0
Net increase (decrease) in cash and cash equivalents													7		3	(302)
Cash and cash equivalents, beginning of year							21					18	21		18	320
Cash and cash equivalents, end of year	28								21				28		21	18
Status of Credit Facility
Commitment	1,426												1,426
Outstanding borrowings	(10)								(19)				(10)		(19)
Amount available	1,416												1,416
Consolidated debt to total capitalization, ratio	0.56												0.56
Related Party Transactions
Current receivables due from affiliates	219								62				219		62
Current payables due to affiliates	106								315				106		315
Long-term payables due to affiliates	98								25				98		25
Senior Notes Due 2017
Cash flows from financing activities:
Interest rate on debt (as a percent)	3.75%												3.75%
Senior Notes Due 2017 | Edison International
Cash flows from financing activities:
Senior notes	400												400
Revolving credit facilities terminating in February 2013 | Southern California Edison Company
Cash flows from financing activities:
Credit facility	2,400												2,400
Revolving credit facilities terminating in February 2013 | Edison International
Cash flows from financing activities:
Credit facility	$ 1,400												$ 1,400
Short-term debt | Edison International
Cash flows from financing activities:
Weighted average interest rate (as a percent)	0.66%								0.63%				0.66%		0.63%

[1] Due to a loss for the three months and year ended December 31, 2011, there are no incremental shares in the diluted computation because such shares would be considered antidilutive.