Edison International (EIX) 10-Q 29 Oct 13 2013 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2013	Oct. 25, 2013
Document And Entity Information [Abstract]
Entity Registrant Name	EDISON INTERNATIONAL
Entity Central Index Key	827052
Current Fiscal Year End Date	-19
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	30-Sep-13
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q3
Amendment Flag	FALSE
Entity Common Stock, Shares Outstanding		325,811,206
Southern California Edison
Document And Entity Information [Abstract]
Entity Registrant Name	SOUTHERN CALIFORNIA EDISON CO
Entity Central Index Key	92103
Current Fiscal Year End Date	-19
Entity Filer Category	Non-accelerated Filer
Document Type	10-Q
Document Period End Date	30-Sep-13
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q3
Amendment Flag	FALSE
Entity Common Stock, Shares Outstanding		434,888,104

Consolidated_Statements_of_Inc

Consolidated Statements of Income (USD $)	3 Months Ended		9 Months Ended
In Millions, except Per Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Operating revenue	$3,960	$3,734	$9,638	$8,802
Fuel	95	83	249	220
Purchased power	1,713	1,612	3,569	3,049
Operation and maintenance	971	993	2,809	2,891
Depreciation, decommissioning and amortization	392	399	1,224	1,187
Asset impairment and other	0	-66	575	-65
Asset impairment			575	0
Total operating expenses	3,171	3,021	8,426	7,282
Operating income	789	713	1,212	1,520
Interest and other income	28	38	91	110
Interest expense	-137	-131	-402	-390
Other expenses	-15	-10	-38	-36
Income from continuing operations before income taxes	665	610	863	1,204
Income tax expense	177	228	173	421
Income from continuing operations	488	382	690	783
Loss from discontinued operations, net of tax	-25	-167	-1	-360
Net income	463	215	689	423
Dividends on preferred and preference stock of utility	25	25	75	66
Net income (loss) attributable to common shareholders	438	190	614	357
Amounts attributable to common shareholders:
Income from continuing operations, net of tax	463	357	615	717
Loss from discontinued operations, net of tax	-25	-167	-1	-360
Net income (loss) attributable to common shareholders	438	190	614	357
Basic earnings (loss) per common share attributable to Edison International common shareholders:
Weighted-average shares of common stock outstanding (in shares)	326	326	326	326
Continuing operations (in dollars per share)	$1.42	$1.09	$1.88	$2.20
Discontinued operations (in dollars per share)	($0.08)	($0.51)	$0	($1.11)
Total (in dollars per share)	$1.34	$0.58	$1.88	$1.09
Diluted earnings (loss) per common share attributable to Edison International common shareholders:
Weighted-average shares of common stock outstanding, including effect of dilutive securities (in shares)	328	329	329	328
Continuing operations (in dollars per share)	$1.41	$1.09	$1.87	$2.18
Discontinued operations (in dollars per share)	($0.07)	($0.51)	$0	($1.09)
Total (in dollars per share)	$1.34	$0.58	$1.87	$1.09
Dividends declared per common share (in dollars per share)	$0.34	$0.33	$1.01	$0.98
Southern California Edison
Operating revenue	3,957	3,731	9,631	8,794
Fuel	95	82	249	220
Purchased power	1,713	1,612	3,569	3,049
Operation and maintenance	875	906	2,540	2,622
Depreciation, decommissioning and amortization	392	399	1,223	1,187
Property and other taxes	78	73	229	229
Asset impairment	0	0	575	0
Total operating expenses	3,153	3,072	8,385	7,307
Operating income	804	659	1,246	1,487
Interest and other income	27	38	89	108
Interest expense	-131	-124	-384	-373
Other expenses	-15	-9	-38	-36
Income from continuing operations before income taxes	685	564	913	1,186
Income tax expense	183	176	196	384
Net income	502	388	717	802
Dividends on preferred and preference stock of utility	25	25	75	66
Net income (loss) attributable to common shareholders	477	363	642	736
Amounts attributable to common shareholders:
Net income (loss) attributable to common shareholders	$477	$363	$642	$736

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Net income	$463	$215	$689	$423
Other comprehensive income (loss), net of tax:
Net loss arising during the period, net of income tax benefit	0	0	-2	-3
Amortization of net loss included in net income, net of income tax expense	3	4	10	12
Unrealized loss on derivatives qualified as cash flow hedges:
Unrealized holding loss arising during the period, net of income tax benefit	0	-16	0	-19
Reclassification adjustments included in net income, net of income tax benefit	0	1	0	-19
Other comprehensive income (loss), net of tax	3	-11	8	-29
Comprehensive income	466	204	697	394
Less: Comprehensive income attributable to noncontrolling interests	25	25	75	66
Comprehensive income attributable to Edison International	441	179	622	328
Southern California Edison
Net income	502	388	717	802
Other comprehensive income (loss), net of tax:
Net loss arising during the period, net of income tax benefit	0	0	-4	-4
Amortization of net loss included in net income, net of income tax expense	2	1	5	5
Unrealized loss on derivatives qualified as cash flow hedges:
Other comprehensive income (loss), net of tax	2	1	1	1
Comprehensive income	$504	$389	$718	$803

Consolidated_Statements_of_Com1

Consolidated Statements of Comprehensive Income (Parenthetical) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Net loss arising during the period, tax benefit	$0	$2	$4	$2
Amortization of net loss included in net income, tax expense	1	1	2	5
Unrealized holding loss arising during the period, tax benefit	0	19	0	2
Reclassification adjustments included in net income, tax benefit	0	6	0	13
Southern California Edison
Net loss arising during the period, tax benefit	0	3	3	3
Amortization of net loss included in net income, tax expense	$1	$1	$2	$3

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
ASSETS
Cash and cash equivalents	$610	$170
Receivables, less allowances of $72 and $75 for uncollectible accounts at respective dates	1,174	762
Accrued unbilled revenue	798	550
Inventory	272	340
Prepaid taxes	27	22
Derivative assets	47	129
Margin and collateral deposits	14	8
Regulatory assets	506	572
Other current assets	155	119
Total current assets	3,603	2,672
Nuclear decommissioning trusts	4,332	4,048
Other investments	201	186
Total investments	4,533	4,234
Utility property, plant and equipment, less accumulated depreciation of $7,817 and $7,424 at respective dates	29,734	30,200
Nonutility property, plant and equipment, less accumulated depreciation of $74 and $123 at respective dates ($68 and $117 for SCE)	75	73
Total property, plant and equipment	29,809	30,273
Derivative assets	207	85
Restricted deposits	4	4
Regulatory assets	8,015	6,422
Other long-term assets	527	704
Total long-term assets	8,753	7,215
Total assets	46,698	44,394
LIABILITIES AND EQUITY
Short-term debt	1,528	175
Current portion of long-term debt	401	0
Accounts payable	1,240	1,423
Accrued taxes	103	61
Accrued interest	102	176
Customer deposits	199	193
Derivative liabilities	174	126
Regulatory liabilities	629	536
Deferred income taxes	159	64
Other current liabilities	854	990
Total current liabilities	5,389	3,744
Long-term debt	9,232	9,231
Deferred income taxes	6,546	6,127
Deferred investment tax credits	106	104
Customer advances	132	149
Derivative liabilities	1,137	939
Pensions and benefits	2,237	2,614
Asset retirement obligations	3,371	2,782
Regulatory liabilities	4,989	5,214
Other deferred credits and other long-term liabilities	2,117	2,299
Total deferred credits and other liabilities	20,635	20,228
Total liabilities	35,256	33,203
Commitments and contingencies (Note 12)
Common stock, no par value (800,000,000 shares authorized; 325,811,206 shares issued and outstanding at each date) and (560,000,000 shares authorized; 434,888,104 shares issued and outstanding at each date for SCE)	2,397	2,373
Accumulated other comprehensive loss	-79	-87
Retained earnings	7,371	7,146
Total common shareholders' equity	9,689	9,432
Preferred and preference stock of utility	1,753	1,759
Total noncontrolling interests	1,753	1,759
Total equity	11,442	11,191
Total liabilities and equity	46,698	44,394
Southern California Edison
ASSETS
Cash and cash equivalents	522	45
Receivables, less allowances of $72 and $75 for uncollectible accounts at respective dates	1,127	755
Accrued unbilled revenue	798	550
Inventory	272	340
Prepaid taxes	22	48
Derivative assets	47	129
Regulatory assets	506	572
Other current assets	167	123
Total current assets	3,461	2,562
Nuclear decommissioning trusts	4,332	4,048
Other investments	130	116
Total investments	4,462	4,164
Utility property, plant and equipment, less accumulated depreciation of $7,817 and $7,424 at respective dates	29,734	30,200
Nonutility property, plant and equipment, less accumulated depreciation of $74 and $123 at respective dates ($68 and $117 for SCE)	70	70
Total property, plant and equipment	29,804	30,270
Derivative assets	207	85
Regulatory assets	8,015	6,422
Other long-term assets	372	531
Total long-term assets	8,594	7,038
Total assets	46,321	44,034
LIABILITIES AND EQUITY
Short-term debt	1,354	175
Current portion of long-term debt	400
Accounts payable	1,228	1,297
Accrued taxes	148	72
Accrued interest	101	172
Customer deposits	199	193
Derivative liabilities	174	126
Regulatory liabilities	629	536
Deferred income taxes	159	81
Other current liabilities	842	861
Total current liabilities	5,234	3,513
Long-term debt	8,828	8,828
Deferred income taxes	7,033	6,669
Deferred investment tax credits	106	104
Customer advances	132	149
Derivative liabilities	1,137	939
Pensions and benefits	1,726	2,245
Asset retirement obligations	3,371	2,782
Regulatory liabilities	4,989	5,214
Other deferred credits and other long-term liabilities	1,774	1,848
Total deferred credits and other liabilities	20,268	19,950
Total liabilities	34,330	32,291
Commitments and contingencies (Note 12)
Common stock, no par value (800,000,000 shares authorized; 325,811,206 shares issued and outstanding at each date) and (560,000,000 shares authorized; 434,888,104 shares issued and outstanding at each date for SCE)	2,168	2,168
Additional paid-in capital	589	581
Accumulated other comprehensive loss	-28	-29
Retained earnings	7,467	7,228
Total common shareholders' equity	10,196	9,948
Preferred and preference stock of utility	1,795	1,795
Total equity	11,991	11,743
Total liabilities and equity	$46,321	$44,034

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, except Share data, unless otherwise specified
Receivables, allowances for uncollectible accounts (in dollars)	$66	$75
Utility property, plant and equipment, accumulated depreciation (in dollars)	7,578	7,424
Nonutility property, plant and equipment, accumulated depreciation (in dollars)	69	123
Common stock, no par value (in dollars per share)	$0	$0
Common stock, shares authorized	800,000,000	800,000,000
Common stock, shares issued	325,811,206	325,811,206
Common stock, shares outstanding	325,811,206	325,811,206
Southern California Edison
Receivables, allowances for uncollectible accounts (in dollars)	66	75
Utility property, plant and equipment, accumulated depreciation (in dollars)	7,578	7,424
Nonutility property, plant and equipment, accumulated depreciation (in dollars)	$63	$117
Common stock, no par value (in dollars per share)	$0	$0
Common stock, shares authorized	560,000,000	560,000,000
Common stock, shares issued	434,888,104	434,888,104
Common stock, shares outstanding	434,888,104	434,888,104

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Cash flows from operating activities:
Net income	$689	$423
Less: Income (loss) from discontinued operations, net of tax	-1	-360
Income from continuing operations	690	783
Adjustments to reconcile to net cash provided by operating activities:
Depreciation, decommissioning and amortization	1,224	1,187
Regulatory impacts of net nuclear decommissioning trust earnings	265	147
Other amortization and other	54	51
Asset impairment	575	0
Gain on sale of assets and other	-2	-65
Stock-based compensation	18	24
Deferred income taxes and investment tax credits	257	176
Proceeds from U.S. treasury grants	0	29
Changes in operating assets and liabilities:
Receivables	-406	-328
Inventory	68	13
Margin and collateral deposits, net of collateral received	-74	6
Prepaid taxes	-5	319
Other current assets	-276	-254
Accounts payable	155	162
Accrued taxes	27	61
Other current liabilities	-130	-124
Derivative assets and liabilities, net	207	1
Regulatory assets and liabilities, net	94	210
Other assets	127	-26
Other liabilities	-615	326
Operating cash flows from continuing operations	2,253	2,698
Operating cash flows from discontinued operations, net	0	-540
Net cash provided by operating activities	2,253	2,158
Cash flows from financing activities:
Long-term debt issued	398	395
Long-term debt issuance costs	-4	-4
Long-term debt repaid	-5	-4
Bonds remarketed, net	195	0
Bonds purchased	-196	0
Preference stock issued, net	387	804
Preference stock redeemed	-400	-75
Short-term debt financing, net	1,352	-31
Settlements of stock-based compensation, net	-40	-34
Dividends to noncontrolling interests	-82	-63
Dividends paid	-330	-318
Financing cash flows from continuing operations	1,275	670
Financing cash flows from discontinued operations, net	0	354
Net cash provided by financing activities	1,275	1,024
Cash flows from investing activities:
Capital expenditures	-2,761	-3,105
Proceeds from sale of nuclear decommissioning trust investments	4,574	1,525
Purchases of nuclear decommissioning trust investments and other	-4,857	-1,689
Proceeds from sale of interest in project, net	0	107
Investments in new businesses	-18	0
Customer advances for construction and other investments	-26	7
Investing cash flows from continuing operations	-3,088	-3,155
Investing cash flows from discontinued operations, net	0	-361
Net cash used by investing activities	-3,088	-3,516
Net (decrease) increase in cash and cash equivalents	440	-334
Cash and cash equivalents at beginning of period	170	1,469
Cash and cash equivalents at end of period	610	1,135
Cash and cash equivalents from discontinued operations	0	753
Cash and cash equivalents from continuing operations	610	382
Southern California Edison
Cash flows from operating activities:
Net income	717	802
Adjustments to reconcile to net cash provided by operating activities:
Depreciation, decommissioning and amortization	1,223	1,187
Regulatory impacts of net nuclear decommissioning trust earnings	265	147
Other amortization	55	55
Asset impairment	575	0
Stock-based compensation	11	13
Deferred income taxes and investment tax credits	197	426
Proceeds from U.S. treasury grants	0	29
Changes in operating assets and liabilities:
Receivables	-371	-336
Inventory	68	13
Margin and collateral deposits, net of collateral received	-74	6
Prepaid taxes	26	230
Other current assets	-279	-295
Accounts payable	174	165
Accrued taxes	76	49
Other current liabilities	-131	-120
Derivative assets and liabilities, net	207	63
Regulatory assets and liabilities, net	94	147
Other assets	142	-26
Other liabilities	-629	101
Net cash provided by operating activities	2,346	2,656
Cash flows from financing activities:
Long-term debt issued	398	395
Long-term debt issuance costs	-4	-4
Long-term debt repaid	-5	-4
Bonds remarketed, net	195	0
Bonds purchased	-196	0
Preference stock issued, net	387	804
Preference stock redeemed	-400	-75
Short-term debt financing, net	1,178	-45
Settlements of stock-based compensation, net	-36	-24
Dividends paid	-321	-411
Net cash provided by financing activities	1,196	636
Cash flows from investing activities:
Capital expenditures	-2,761	-3,105
Proceeds from sale of nuclear decommissioning trust investments	4,574	1,525
Purchases of nuclear decommissioning trust investments and other	-4,857	-1,689
Customer advances for construction and other investments	-21	10
Net cash used by investing activities	-3,065	-3,259
Net (decrease) increase in cash and cash equivalents	477	33
Cash and cash equivalents at beginning of period	45	57
Cash and cash equivalents at end of period	$522	$90

Summary_of_Significant_Account

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2013
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies
	Organization and Basis of Presentation
	Edison International is the parent holding company of Southern California Edison Company ("SCE"). SCE is an investor-owned public utility primarily engaged in the business of supplying electricity to an approximately 50,000 square mile area of southern California. Edison International is also the parent company of nonutility subsidiaries that are engaged in competitive businesses related to the delivery or use of electricity. Such competitive business activities are currently not material to report as a separate business segment. These combined notes to the consolidated financial statements apply to both Edison International and SCE unless otherwise described. Edison International's consolidated financial statements include the accounts of Edison International, SCE and other wholly owned and controlled subsidiaries. References to Edison International refer to the consolidated group of Edison International and its subsidiaries. References to Edison International Parent and Other refer to Edison International Parent and its nonutility subsidiaries. SCE's consolidated financial statements include the accounts of SCE and its wholly owned and controlled subsidiaries. All intercompany transactions have been eliminated from the consolidated financial statements.
	Edison International's and SCE's significant accounting policies were described in Note 1 of "Notes to Consolidated Financial Statements" included in the 2012 Form 10-K. The same accounting policies are followed for interim reporting purposes, with the exception of accounting principles adopted as of January 1, 2013, discussed below in "—New Accounting Guidance." This quarterly report should be read in conjunction with the financial statements and notes included in the 2012 Form 10-K.
	Beginning in the fourth quarter of 2012, Edison Mission Energy ("EME") met the definition of a discontinued operation and was classified separately in Edison International's consolidated financial statements. Except as indicated, amounts in the notes to the consolidated financial statements relate to continuing operations of Edison International. See Note 16 for information related to discontinued operations.
	In the opinion of management, all adjustments, consisting of recurring accruals, have been made that are necessary to fairly state the consolidated financial position, results of operations and cash flows in accordance with accounting principles generally accepted in the United States of America for the periods covered by this quarterly report on Form 10-Q. The results of operations for the three- and nine-month periods ended September 30, 2013 are not necessarily indicative of the operating results for the full year.
	The December 31, 2012 condensed consolidated balance sheet data was derived from audited financial statements, but does not include all disclosures required by accounting principles generally accepted in the United States of America.
	Cash Equivalents
	Cash equivalents included investments in money market funds. Generally, the carrying value of cash equivalents equals the fair value, as these investments have original maturities of three months or less. The cash equivalents were as follows:
		Edison International					SCE
	(in millions)	September 30,		December 31, 2012			September 30,		December 31, 2012
		2013					2013
	Money market funds	$	518	$	107		$	453	$	5
	Cash is temporarily invested until required for check clearing from the primary disbursement accounts. Checks issued, but not yet paid by the financial institution, are reclassified from cash to accounts payable at the end of each reporting period as follows:
		Edison International					SCE
	(in millions)	September 30,		December 31, 2012			September 30,		December 31, 2012
		2013					2013
	Uncleared checks reclassified to accounts payable	$	202	$	247		$	201	$	242
	Inventory
	Inventory is stated at the lower of cost or market, cost being determined by the weighted-average cost method for fuel, and the average cost method for materials, supplies and spare parts. Inventory consisted of the following:
	(in millions)	September 30,		December 31, 2012
		2013
	Materials, supplies and spare parts	$	250	$	319
	Fuel	22		21
	Total inventory	$	272	$	340
	As a result of the permanent retirement of San Onofre, SCE has reclassified $100 million of its inventory to a regulatory asset, see Note 9 for further details.
	Greenhouse Gas Allowances
	SCE is allocated greenhouse gas ("GHG") allowances annually which it is then required to sell them into quarterly auctions. GHG proceeds from the auction are recorded as a regulatory liability to be refunded to customers. SCE purchases GHG allowances from quarterly auctions or bilateral parties to satisfy its compliance obligations and recovers such costs of GHG from customers. GHG allowances held for use are classified as "Other current assets" on the consolidated balance sheets and are stated at the lower of weighted-average cost or market.
	Earnings Per Share
	Edison International computes earnings per share ("EPS") using the two-class method, which is an earnings allocation formula that determines EPS for each class of common stock and participating security. Edison International's participating securities are stock-based compensation awards payable in common shares, including stock options, performance shares and restricted stock units, which earn dividend equivalents on an equal basis with common shares. Stock options awarded during the period 2003 through 2006 received dividend equivalents. EPS attributable to Edison International common shareholders was computed as follows:
		Three months ended September 30,					Nine months ended
							September 30,
	(in millions)	2013		2012			2013		2012
	Basic earnings per share – continuing operations:
	Income from continuing operations available to common shareholders	$	463	$	357		$	615	$	717
	Weighted average common shares outstanding	326		326			326		326
	Basic earnings per share – continuing operations	$	1.42	$	1.09		$	1.88	$	2.2
	Diluted earnings per share – continuing operations:
	Income from continuing operations available to common shareholders	$	463	$	357		$	615	$	717
	Income impact of assumed conversions	—		—			1		—
	Income from continuing operations available to common shareholders and assumed conversions	$	463	$	357		$	616	$	717
	Weighted average common shares outstanding	326		326			326		326
	Incremental shares from assumed conversions	2		3			3		2
	Adjusted weighted average shares – diluted	328		329			329		328
	Diluted earnings per share – continuing operations	$	1.41	$	1.09		$	1.87	$	2.18
	Stock-based compensation awards to purchase 4,109,363 and 3,238,581 shares of common stock for the three months ended September 30, 2013 and 2012, respectively, and 4,109,363 and 4,819,683 for the nine months ended September 30, 2013 and 2012, respectively, were outstanding, but were not included in the computation of diluted earnings per share because the exercise price of the awards was greater than the average market price of the common shares during the respective periods and, therefore, the effect would have been antidilutive.
	Asset Retirement Obligation
	SCE is in the process of developing a comprehensive decommissioning plan following its decision to permanently retire San Onofre. See Note 9 for further details. The asset retirement obligation ("ARO") liability related to San Onofre increased by $455 million in the second quarter of 2013 based on an updated decommissioning cost estimate for the retirement of both San Onofre Units 2 and 3. The ARO liability related to San Onofre at September 30, 2013 was $2.71 billion.
	The following table summarizes the changes in SCE's ARO liability, including San Onofre and Palo Verde:
	(in millions)	September 30,		December 31,
		2013		2012
	Beginning balance	$	2,782	$	2,610
	Accretion expense1	134		161
	Revisions	455		12
	Liabilities settled	—		(1		)
	Ending balance	$	3,371	$	2,782
	1	An asset retirement obligation represents the present value of a future obligation. Accretion expense is an increase in the liability to account for the time value of money resulting from discounting.
	Related-Party Transactions
	In 2008, EME was awarded by SCE, through a competitive bidding process, a 10-year power sales contract with SCE for the output of a 479 MW gas-fired peaking facility referred to as the Walnut Creek project. The power sales agreement was approved by the CPUC and FERC in 2008. Deliveries under the power sales agreement commenced in June 2013 and the expense for power purchased was $64 million and $70 million for the three- and nine-months ended September 30, 2013, respectively.
	New Accounting Guidance
	Accounting Guidance Adopted in 2013
	Offsetting Assets and Liabilities
	In January 2013, the FASB issued accounting standard updates modifying the disclosure requirements about the nature of an entity's rights of offsetting recognized assets and liabilities in the statement of financial position under master netting agreements and similar arrangements associated with derivative instruments, repurchase agreements and securities lending transactions. The guidance requires increased disclosure of the gross and net recognized assets and liabilities, collateral positions and descriptions of setoff rights. Edison International and SCE adopted this guidance effective January 1, 2013. The adoption of this standard did not impact the consolidated income statements, balance sheets or cash flows of Edison International or SCE. See Note 6 for further details.
	Items Reclassified out of Accumulated Other Comprehensive Income
In February 2013, the FASB issued an accounting standards update which requires disclosure related to items reclassified out of accumulated other comprehensive income ("AOCI"). The guidance requires companies to present separately, for each component of other comprehensive income, current period reclassifications and the remainder of the current-period other comprehensive income. In addition, for certain current period reclassifications, an entity is required to disclose the effect of the item reclassified out of AOCI on the respective line item(s) of net income. Edison International and SCE adopted this guidance effective January 1, 2013. See Note 14 for further details.
Accounting Guidance Not Yet Adopted
In July 2013, the FASB issued an accounting standards update that will require that an unrecognized tax benefit be presented on the balance sheet as a reduction of a deferred tax asset for a net operating loss ("NOL") or tax credit carryforward under certain circumstances. This proposal is effective January 1, 2014 and is not expected to have a material impact on the consolidated financial statements.

Consolidated_Statements_of_Cha

Consolidated Statements of Changes in Equity (Notes)	9 Months Ended
	Sep. 30, 2013
Statement of Stockholders' Equity [Abstract]
Consolidated Statements of Changes in Equity	Consolidated Statements of Changes in Equity
	The following table provides Edison International's changes in equity for the nine months ended September 30, 2013:
		Equity Attributable to Edison International																Noncontrolling Interests
	(in millions)	Common				Accumulated				Retained				Subtotal				Preferred				Total
		Stock				Other				Earnings								and				Equity
						Comprehensive												Preference
						Loss												Stock
	Balance at December 31, 2012	$	2,373			$	(87	)		$	7,146			$	9,432			$	1,759			$	11,191
	Net income	—				—				614				614				75				689
	Other comprehensive income	—				8				—				8				—				8
	Common stock dividends declared ($1.0125 per share)	—				—				(330		)		(330		)		—				(330		)
	Dividends, distributions to noncontrolling interests	—				—				—				—				(75		)		(75		)
	Stock-based compensation and other	5				—				(45		)		(40		)		—				(40		)
	Noncash stock-based compensation and other	19				—				(6		)		13				(1		)		12
	Issuance of preference stock	—				—				—				—				387				387
	Redemption of preference stock	—				—				(8		)		(8		)		(392		)		(400		)
	Balance at September 30, 2013	$	2,397			$	(79	)		$	7,371			$	9,689			$	1,753			$	11,442
	During the first quarter of 2013, SCE redeemed all outstanding shares of Series B and C preference stock and charged the issuance costs to retained earnings.
	The following table provides Edison International's changes in equity for the nine months ended September 30, 2012:
		Equity Attributable to Edison International															Noncontrolling Interests
	(in millions)	Common			Accumulated				Retained				Subtotal				Other				Preferred				Total
		Stock			Other				Earnings												and				Equity
					Comprehensive																Preference
					Loss																Stock
	Balance at December 31, 2011	$	2,360		$	(139	)		$	7,834			$	10,055			$	2			$	1,029			$	11,086
	Net income	—			—				357				357				—				66				423
	Other comprehensive loss	—			(29		)		—				(29		)		—				—				(29		)
	Contributions from noncontrolling interests	—			—				—				—				238				—				238
	Transfer of assets to Capistrano Wind Partners	(21		)	—				—				(21		)		—				—				(21		)
	Common stock dividends declared ($0.975 per share)	—			—				(318		)		(318		)		—				—				(318		)
	Dividends, distributions to noncontrolling interests and other	—			—				—				—				(2		)		(66		)		(68		)
	Stock-based compensation and other	19			—				(64		)		(45		)		—				—				(45		)
	Noncash stock-based compensation and other	27			—				(2		)		25				—				—				25
	Issuance of preference stock	—			—				—				—				—				804				804
	Redemption of preference stock	—			—				(1		)		(1		)		—				(74		)		(75		)
	Balance at September 30, 2012	$	2,385		$	(168	)		$	7,806			$	10,023			$	238			$	1,759			$	12,020
	The following table provides SCE's changes in equity for the nine months ended September 30, 2013:
		Equity Attributable to SCE
	(in millions)	Common				Additional				Accumulated				Retained				Preferred				Total
		Stock				Paid-in				Other				Earnings				and				Equity
						Capital				Comprehensive								Preference
										Loss								Stock
	Balance at December 31, 2012	$	2,168			$	581			$	(29	)		$	7,228			$	1,795			$	11,743
	Net income	—				—				—				717				—				717
	Other comprehensive income	—				—				1				—				—				1
	Dividends declared on common stock	—				—				—				(360		)		—				(360		)
	Dividends declared on preferred and preference stock	—				—				—				(75		)		—				(75		)
	Stock-based compensation and other	—				3				—				(39		)		—				(36		)
	Noncash stock-based compensation and other	—				10				—				4				—				14
	Issuance of preference stock	—				(13		)		—				—				400				387
	Redemption of preference stock	—				8				—				(8		)		(400		)		(400		)
	Balance at September 30, 2013	$	2,168			$	589			$	(28	)		$	7,467			$	1,795			$	11,991
	During the first quarter of 2013, SCE redeemed all outstanding shares of Series B and C preference stock and charged the issuance costs to retained earnings.
	The following table provides SCE's changes in equity for the nine months ended September 30, 2012:
		Equity Attributable to SCE
	(in millions)	Common				Additional				Accumulated				Retained				Preferred				Total
		Stock				Paid-in				Other				Earnings				and				Equity
						Capital				Comprehensive								Preference
										Loss								Stock
	Balance at December 31, 2011	$	2,168			$	596			$	(24	)		$	6,173			$	1,045			$	9,958
	Net income	—				—				—				802				—				802
	Other comprehensive income	—				—				1				—				—				1
	Dividends declared on common stock	—				—				—				(349		)		—				(349		)
	Dividends declared on preferred and preference stock	—				—				—				(66		)		—				(66		)
Stock-based compensation and other	—				11				—				(35		)		—				(24		)
Noncash stock-based compensation and other	—				13				—				—				—				13
Issuance of preference stock	—				(21		)		—				—				825				804
Redemption of preference stock	—				1				—				(1		)		(75		)		(75		)
Balance at September 30, 2012	$	2,168			$	600			$	(23	)		$	6,524			$	1,795			$	11,064

Variable_Interest_Entities

Variable Interest Entities	9 Months Ended
	Sep. 30, 2013
Variable Interest Entities Disclosure [Abstract]
Variable Interest Entities	Variable Interest Entities
	Variable Interest in VIEs that are not Consolidated
	Power Purchase Contracts
	SCE has power purchase agreements ("PPAs") that are classified as variable interests in variable interest entities ("VIEs"), including tolling agreements through which SCE provides the natural gas to fuel the plants and contracts with qualifying facilities ("QFs") that contain variable pricing provisions based on the price of natural gas. SCE has concluded that it is not the primary beneficiary of these VIEs since it does not control the commercial and operating activities of these entities. In general, because payments for capacity are the primary source of income, the most significant economic activity for these VIEs is the operation and maintenance of the power plants.
	As of the balance sheet date, the carrying amount of assets and liabilities in SCE's consolidated balance sheet that relate to its involvement with VIEs result from amounts due under the PPAs or the fair value of those derivative contracts. Under these contracts, SCE recovers the costs incurred through demonstration of compliance with its CPUC-approved long-term power procurement plans. SCE has no residual interest in the entities and has not provided or guaranteed any debt or equity support, liquidity arrangements, performance guarantees or other commitments associated with these contracts other than the purchase commitments described in Note 9 in the 2012 Form 10-K. As a result, there is no significant potential exposure to loss to SCE from its variable interest in these VIEs. The aggregate contracted capacity dedicated to SCE for these VIE projects was 5,290 MW and 2,094 MW at September 30, 2013 and 2012, respectively, and the amounts that SCE paid to these projects were $330 million and $158 million for the three months ended September 30, 2013 and 2012, respectively, and $527 million and $292 million for the nine months ended September 30, 2013 and 2012, respectively. These amounts are recoverable in customer rates, subject to reasonableness review.
	Unconsolidated Trusts of SCE
	SCE Trust I and Trust II were formed in 2012 and 2013, respectively, for the exclusive purpose of issuing the 5.625% and 5.10% trust preference securities, respectively (“trust securities”). The trusts are VIEs. SCE has concluded that it is not the primary beneficiary of these VIEs as it does not have the obligation to absorb the expected losses or the right to receive the expected residual returns of the trusts.
	In May 2012, SCE Trust I issued $475 million (aggregate liquidation preference) of 5.625% trust securities (cumulative, liquidation amount of $25 per share) to the public and $10,000 of common stock (100%) to SCE. The trust invested the proceeds of these trust securities in Series F Preference Stock issued by SCE in the principal amount of $475 million (cumulative, $2,500 per share liquidation value) and which have substantially the same payment terms as the trust securities.
	In January 2013, SCE Trust II issued $400 million (aggregate liquidation preference) of 5.10% trust securities (cumulative, liquidation amount of $25 per share) to the public and $10,000 of common stock (100%) to SCE. The trust invested the proceeds of these trust securities in Series G Preference Stock issued by SCE in the principal amount of $400 million (cumulative, $2,500 per share liquidation value) and which have substantially the same payment terms as the trust securities.
	The Series F and Series G Preference Stock and the corresponding trust securities do not have a maturity date. Upon any redemption of any shares of the Series F or Series G Preference Stock, a corresponding dollar amount of trust securities will be redeemed by the applicable trust (for further information see Note 13). The applicable trust will make distributions at the same rate and on the same dates on the applicable series of trust securities when and if the SCE board of directors declares and makes dividend payments on the Series F or Series G Preference Stock. The applicable trusts will use any dividends it receives on the Series F or Series G Preference Stock to make its corresponding distributions on the applicable series of trust securities. If SCE does not make a dividend payment to either trust, SCE would be prohibited from paying dividends on its common stock. SCE has fully and unconditionally guaranteed the payment of the trust securities and trust distributions, if and when SCE pays dividends on the Series F and Series G Preference Stock.
	The Trust I balance sheet as of September 30, 2013 and December 31, 2012, consisted of an investment of $475 million in the Series F Preference Stock, $475 million of trust securities and $10,000 of common stock. The trust's income statement consisted of dividend income and dividend distributions of $7 million and $7 million each for the three months ended September 30, 2013 and 2012, respectively, and $20 million and $10 million each for the nine months ended September 30, 2013 and 2012, respectively.
	The Trust II balance sheet as of September 30, 2013, consisted of an investment of $400 million in the Series G Preference Stock, $400 million of trust securities and $10,000 of common stock. The trust's income statement consisted of dividend income and dividend distributions of $5 million each for the three months ended September 30, 2013 and $14 million each for the nine months ended September 30, 2013.

Fair_Value_Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2013
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements
	Recurring Fair Value Measurements
	Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (referred to as an “exit price”). Fair value of an asset or liability considers assumptions that market participants would use in pricing the asset or liability, including assumptions about nonperformance risk. As of September 30, 2013 and December 31, 2012, nonperformance risk was not material for Edison International and SCE.
	Assets and liabilities are categorized into a three-level fair value hierarchy based on valuation inputs used to determine fair value. The hierarchy gives the highest priority to unadjusted quoted market prices in active markets for identical assets and liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements).
	SCE
	The following table sets forth assets and liabilities of SCE that were accounted for at fair value by level within the fair value hierarchy:
		September 30, 2013
	(in millions)	Level 1				Level 2				Level 3				Netting				Total
														and
														Collateral1
	Assets at fair value
	Money market funds	$	453			$	—			$	—			$	—			$	453
	Mutual funds	29				—				—				—				29
	Derivative contracts:
	Congestion revenue rights	—				—				245				—				245
	Electricity	—				1				—				—				1
	Natural gas	—				1				—				(1		)		—
	Tolling	—				—				8				—				8
	Subtotal of derivative contracts	—				2				253				(1		)		254
	Long-term disability plan	8				—				—				—				8
	Nuclear decommissioning trusts:
	Stocks2	2,027				—				—				—				2,027
	U.S. government and agency securities	823				101				—				—				924
	Municipal bonds	—				796				—				—				796
	Corporate bonds	—				221				—				—				221
	Short-term investments, primarily cash equivalents4	322				45				—				—				367
	Subtotal of nuclear decommissioning trusts	3,172				1,163				—				—				4,335
	Total assets	3,662				1,165				253				(1		)		5,079
	Liabilities at fair value
	Derivative contracts:
	Electricity	—				5				12				(3		)		14
	Natural gas	—				43				—				(18		)		25
	Tolling	—				—				1,272				—				1,272
	Subtotal of derivative contracts	—				48				1,284				(21		)		1,311
	Total liabilities	—				48				1,284				(21		)		1,311
	Net assets (liabilities)	$	3,662			$	1,117			$	(1,031	)		$	20			$	3,768
		December 31, 2012
	(in millions)	Level 1				Level 2				Level 3				Netting				Total
														and
														Collateral1
	Assets at fair value
	Money market funds	$	5			$	—			$	—			$	—			$	5
	Derivative contracts:
	Congestion revenue rights	—				—				186				—				186
	Electricity	—				—				31				(13		)		18
	Natural gas	—				8				—				(2		)		6
	Tolling	—				—				4				—				4
	Subtotal of derivative contracts	—				8				221				(15		)		214
	Long-term disability plan	8				—				—				—				8
	Nuclear decommissioning trusts:
	Stocks2	2,271				—				—				—				2,271
	Municipal bonds	—				644				—				—				644
	U.S. government and agency securities	477				126				—				—				603
	Corporate bonds	—				410				—				—				410
	Short-term investments, primarily cash equivalents4	121				—				—				—				121
	Subtotal of nuclear decommissioning trusts	2,869				1,180				—				—				4,049
	Total assets	2,882				1,188				221				(15		)		4,276
	Liabilities at fair value
	Derivative contracts:
	Electricity	—				2				5				(2		)		5
	Natural gas	—				113				2				(60		)		55
	Tolling	—				—				1,005				—				1,005
	Subtotal of derivative contracts	—				115				1,012				(62		)		1,065
	Total liabilities	—				115				1,012				(62		)		1,065
Net assets (liabilities)	$	2,882			$	1,073			$	(791	)		$	47			$	3,211
1	Represents the netting of assets and liabilities under master netting agreements and cash collateral across the levels of the fair value hierarchy. Netting among positions classified within the same level is included in that level.
2	Approximately 69% and 66% of SCE's equity investments were located in the United States at September 30, 2013 and December 31, 2012, respectively.
3	At September 30, 2013 and December 31, 2012, SCE's corporate bonds were diversified and included collateralized mortgage obligations and other asset backed securities of $32 million and $56 million, respectively.
4	Excludes net payables of $3 million and $1 million at September 30, 2013 and December 31, 2012, respectively, of interest and dividend receivables as well as receivables and payables related to SCE's pending securities sales and purchases.
Edison International Parent and Other
Assets measured at fair value consisted of money market funds of $518 million and $107 million at September 30, 2013 and December 31, 2012, respectively, classified as Level 1.
SCE Fair Value of Level 3
The following table sets forth a summary of changes in SCE's fair value of Level 3 net derivative assets and liabilities:
		Three months ended September 30,								Nine months ended
										September 30,
(in millions)		2013				2012				2013				2012
Fair value of net liabilities at beginning of period		$	(967	)		$	(739	)		$	(791	)		$	(754	)
Total realized/unrealized gains (losses):
Included in regulatory assets and liabilities1		(50		)		(180		)		(205		)		(203		)
Purchases		19				33				56				84
Settlements		(33		)		(44		)		(91		)		(57		)
Fair value of net liabilities at end of period		$	(1,031	)		$	(930	)		$	(1,031	)		$	(930	)
Change during the period in unrealized losses related to assets and liabilities held at the end of the period		$	(65	)		$	(222	)		$	(198	)		$	(244	)
1	Due to regulatory mechanisms, SCE's realized and unrealized gains and losses are recorded as regulatory assets and liabilities.
Edison International and SCE recognize the fair value for transfers in and transfers out of each level at the end of each reporting period. There were no transfers between any levels during 2013 and 2012.
Valuation Techniques Used to Determine Fair Value
Level 1
The fair value of Edison International and SCE's Level 1 assets and liabilities is determined using unadjusted quoted prices in active markets that are available at the measurement date for identical assets and liabilities. This level includes exchange-traded equity securities and derivatives, U.S. treasury securities, mutual funds and money market funds.
Level 2
SCE's Level 2 assets and liabilities include fixed income securities and over-the-counter derivatives. The fair value of fixed income securities is determined using a market approach by obtaining quoted prices for similar assets and liabilities in active markets and inputs that are observable, either directly or indirectly, for substantially the full term of the instrument. For further discussion on fixed income securities, see "—Nuclear Decommissioning Trusts" below.
The fair value of SCE's over-the-counter derivative contracts is determined using an income approach. SCE uses standard pricing models to determine the net present value of estimated future cash flows. Inputs to the pricing models include forward published or posted clearing prices from exchanges (New York Mercantile Exchange and Intercontinental Exchange) for similar instruments and discount rates. A primary price source that best represents trade activity for each market is used to develop observable forward market prices in determining the fair value of these positions. Broker quotes, prices from exchanges or comparison to executed trades are used to validate and corroborate the primary price source. These price quotations reflect mid-market prices (average of bid and ask) and are obtained from sources believed to provide the most liquid market for the commodity.
Level 3
The fair value of SCE's Level 3 assets and liabilities is determined using the income approach through various models and techniques that require significant unobservable inputs. This level includes over-the-counter options, tolling arrangements and derivative contracts that trade infrequently such as congestion revenue rights ("CRRs") and long-term power agreements.
Assumptions are made in order to value derivative contracts in which observable inputs are not available. Changes in fair value are based on changes to forward market prices, including extrapolation of short-term observable inputs into forecasted prices for illiquid forward periods. In circumstances where fair value cannot be verified with observable market transactions, it is possible that a different valuation model could produce a materially different estimate of fair value. Modeling methodologies, inputs and techniques are reviewed and assessed as markets continue to develop and more pricing information becomes available and the fair value is adjusted when it is concluded that a change in inputs or techniques would result in a new valuation that better reflects the fair value of those derivative contracts.
Level 3 Valuation Process
The process of determining fair value is the responsibility of SCE's risk management department, which reports to SCE's chief financial officer. This department obtains observable and unobservable inputs through broker quotes, exchanges and internal valuation techniques that use both standard and proprietary models to determine fair value. Each reporting period, the risk and finance departments collaborate to determine the appropriate fair value methodologies and classifications for each derivative. Inputs are validated for reasonableness by comparison against prior prices, other broker quotes and volatility fluctuation thresholds. Inputs used and valuations are reviewed period-over-period and compared with market conditions to determine reasonableness.
The following table sets forth SCE's valuation techniques and significant unobservable inputs used to determine fair value for Level 3 assets and liabilities:
	Fair Value (in millions)								Significant	Range
September 30, 2013	Assets				Liabilities			Valuation Technique(s)	Unobservable Input	(Weighted Average)
Electricity:
Options	$	2			$	10		Option model	Volatility of gas prices	24% - 30% (28%)
									Volatility of power prices	28% - 45% (39%)
									Power prices	$40.60 - $49.80 ($43.50)
Forwards	—				4			Discounted cash flow	Power prices	$7.70 - $40.80 ($31.40)
CRRs	245				—			Market simulation model	Load forecast	7,603 MW - 24,896 MW
									Power prices	$(9.86) - $108.56
									Gas prices	$3.50 - $7.10
Tolling	8				1,272			Option model	Volatility of gas prices	16% - 30% (19%)
									Volatility of power prices	25% - 45% (29%)
									Power prices	$35.90 - $62.60 ($46.90)
Netting	(2		)		(2		)
Total derivative contracts	$	253			$	1,284
	Fair Value (in millions)								Significant	Range
31-Dec-12	Assets				Liabilities			Valuation Technique(s)	Unobservable Input	(Weighted Average)
Electricity:
Options	$	40			$	12		Option model	Volatility of gas prices	25% - 36% (33%)
									Volatility of power prices	29% - 64% (42%)
									Power prices	$41.70 - $59.20 ($47.00)
Forwards	2				4			Discounted cash flow	Power prices	$23.10 - $44.90 ($31.10)
CRRs	186				—			Market simulation model	Load forecast	7,597 MW - 26,612 MW
									Power prices	$(13.90) - $226.75
									Gas prices	$2.95 - $7.78
Gas options	—				2			Option model	Volatility of gas prices	28% - 36% (34%)
Tolling	4				1,005			Option model	Volatility of gas prices	17% - 36% (22%)
									Volatility of power prices	26% - 64% (29%)
									Power prices	$35.00 - $84.10 ($55.40)
Netting	(11		)		(11		)
Total derivative contracts	$	221			$	1,012
Level 3 Fair Value Sensitivity
Gas Options, Electricity Options, and Tolling Arrangements
The fair values of SCE's option contracts and tolling arrangements contain intrinsic value and time value. Intrinsic value is the difference between the market price and strike price of the underlying commodity. Time value is made up of several components, including volatility, time to expiration, and interest rates. The fair value of option contracts changes as the underlying commodity price moves away or towards the strike price. The option model for tolling arrangements reflects plant specific information such as operating and start-up costs.
For tolling arrangements and certain gas and power option contracts where SCE is the buyer, increases in volatility of the underlying commodity prices would result in increases to fair value as it represents greater price movement risk. As power and gas prices increase, the fair value of the option contracts and tolling arrangements tends to increase. The valuation of power option contracts and tolling arrangements is also impacted by the correlation between gas and power prices. As the correlation increases, the fair value of power option contracts and tolling arrangements tends to decline.
Forward Power Contracts
Generally, an increase (decrease) in long-term forward power prices at illiquid locations where SCE is the buyer relative to the contract price will increase (decrease) fair value.
Congestion Revenue Rights
Where SCE is the buyer, generally increases (decreases) in forecasted load in isolation would result in increases (decreases) to the fair value. In general, an increase (decrease) in electricity and gas prices at illiquid locations tends to result in increases (decreases) to fair value; however, changes in electricity and gas prices in opposite directions may have varying results on fair value.
Nuclear Decommissioning Trusts
SCE's nuclear decommissioning trust investments include equity securities, U.S. treasury securities and other fixed income securities. Equity and treasury securities are classified as Level 1 as fair value is determined by observable market prices in active or highly liquid and transparent markets. The remaining fixed income securities are classified as Level 2. The fair value of these financial instruments is based on evaluated prices that reflect significant observable market information such as reported trades, actual trade information of similar securities, benchmark yields, broker/dealer quotes, issuer spreads, bids, offers and relevant credit information.
Fair Value of Long-Term Debt Recorded at Carrying Value
The carrying value and fair value of Edison International and SCE's long-term debt is as follows:
	September 30, 2013								December 31, 2012
(in millions)	Carrying				Fair				Carrying				Fair
	Value				Value				Value				Value
SCE	$	8,828			$	9,590			$	8,828			$	10,505
Edison International	9,232				10,016				9,231				10,944
Fair value of Edison International and SCE's short-term and long-term debt is classified as Level 2 and is based on evaluated prices that reflect significant observable market information such as reported trades, actual trade information of similar securities, benchmark yields, broker/dealer quotes of new issue prices and relevant credit information.
The carrying value of Edison International and SCE's trade receivables and payables, other investments, and short-term debt approximates fair value.

Debt_and_Credit_Agreements

Debt and Credit Agreements	9 Months Ended
	Sep. 30, 2013
Debt Disclosure [Abstract]
Debt and Credit Agreements	Debt and Credit Agreements
	Long-Term Debt
	In March 2013, SCE issued $400 million of 3.90% first and refunding mortgage bonds due in 2043. The proceeds from these bonds were used to repay commercial paper borrowings and to fund SCE's capital program.
	Credit Agreements and Short-Term Debt
	In July 2013, SCE and Edison International Parent amended their credit facilities to extend the maturity dates to July 2018 for $2.6 billion and $1.182 billion, respectively. The remaining $150 million and $68 million of the SCE and Edison International Parent credit facilities, respectively, will mature in May 2017.
	At September 30, 2013, SCE's outstanding commercial paper was $1.35 billion at a weighted-average interest rate of 0.25%. This commercial paper was supported by a $2.75 billion multi-year revolving credit facility. At September 30, 2013, letters of credit issued under SCE's credit facility aggregated $140 million and are scheduled to expire in twelve months or less. At December 31, 2012, the outstanding commercial paper was $175 million at a weighted-average interest rate of 0.37%.
	At September 30, 2013, Edison International Parent's outstanding short-term debt was $174 million at a weighted-average interest rate of 1.46%. This short-term debt was supported by a $1.25 billion multi-year revolving credit facility. At December 31, 2012, Edison International had no outstanding short-term debt.
	Financing Subsequent to September 30, 2013
	In October 2013, SCE issued $200 million of floating rate due in 2014, $600 million of 3.50% due in 2023, and $800 million of 4.65% first and refunding mortgage bonds due in 2043. The proceeds from these bonds were used to redeem $800 million of outstanding first mortgage bonds in October 2013 (due in March 2014), to repay commercial paper borrowings and to fund SCE's capital program.

Derivative_Instruments

Derivative Instruments	9 Months Ended
	Sep. 30, 2013
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities	Derivative Instruments
	Derivative financial instruments are used to manage exposure to commodity price risk. SCE manages commodity price risk in part by entering into forward commodity transactions, including options, swaps and forwards, tolling arrangements and CRRs. To mitigate credit and default risk SCE enters into master netting agreements or similar agreements whenever possible. These transactions are approved by the CPUC or executed in compliance with CPUC-approved procurement plans. SCE recovers its related hedging costs through the energy resource recovery account ("ERRA"), and as a result, exposure to commodity price and credit and default risks are not expected to impact earnings, but may impact cash flows.
	Commodity Price Risk
	Commodity price risk represents the potential impact that can be caused by a change in the market value of a particular commodity. SCE's electricity price exposure arises from energy purchased from and sold to wholesale markets as a result of differences between SCE's load requirements and the amount of energy delivered from its generating facilities and power purchase agreements. SCE's natural gas price exposure arises from natural gas purchased for the Mountainview power plant and peaker plants, QF contracts where pricing is based on a monthly natural gas index and power purchase agreements in which SCE has agreed to provide the natural gas needed for generation, referred to as tolling arrangements.
	Credit and Default Risk
	Credit and default risk represents the potential impact that can be caused if a counterparty were to default on its contractual obligations and SCE would be exposed to spot markets for buying replacement power or selling excess power. In addition, SCE would be exposed to the risk of non-payment of accounts receivable, primarily related to the sales of excess power and realized gains on derivative instruments.
	Certain power contracts contain master netting agreements or similar agreements, which generally allows counterparties subject to the agreement to set-off amounts when certain criteria are met, such as in the event of default. The objective of netting is to reduce credit exposure. Additionally, to reduce SCE's risk exposures counterparties may be required to pledge collateral depending on the creditworthiness of each counterparty and the risk associated with the transaction.
	Certain power contracts contain a provision that requires SCE to maintain an investment grade credit rating from each of the major credit rating agencies, referred to as a credit-risk-related contingent feature. If SCE's credit rating were to fall below investment grade, SCE may be required to pay the derivative liability or post additional collateral. The net fair value of all derivative liabilities with these credit-risk-related contingent features was $53 million and $6 million as of September 30, 2013 and December 31, 2012, respectively, for which SCE has posted no collateral to its counterparties for the respective periods. If the credit-risk-related contingent features underlying these agreements were triggered on September 30, 2013, SCE would be required to post collateral in the amount of $14 million, excluding the impact of unpaid closed positions as their settlement is not impacted by the credit-risk-related contingent features.
	Fair Value of Derivative Instruments
	SCE presents its derivative assets and liabilities on a net basis on its consolidated balance sheets when subject to master netting agreements or similar agreements. Derivative positions are offset against margin and cash collateral deposits. In addition, SCE has provided collateral in the form of letters of credit. Collateral requirements can vary depending upon the level of unsecured credit extended by counterparties, changes in market prices relative to contractual commitments and other factors. The following table summarizes the gross and net fair values of SCE's commodity derivative instruments:
			September 30, 2013
			Derivative Assets										Derivative Liabilities
	(in millions)		Short-Term				Long-Term			Subtotal			Short-Term			Long-Term			Subtotal			Net
																						Liability
	Commodity derivative contracts
	Gross amounts recognized		$	53			$	207		$	260		$	195		$	1,143		$	1,338		$	1,078
	Gross amounts offset in the consolidated balance sheets		(6		)		—			(6		)	(6		)	—			(6		)	—
	Cash collateral posted1		—				—			—			(15		)	(6		)	(21		)	(21		)
	Net amounts presented in the consolidated balance sheets		$	47			$	207		$	254		$	174		$	1,137		$	1,311		$	1,057
			December 31, 2012
			Derivative Assets										Derivative Liabilities
	(in millions)		Short-Term				Long-Term			Subtotal			Short-Term			Long-Term			Subtotal			Net
																						Liability
	Commodity derivative contracts
	Gross amounts recognized		$	151			$	91		$	242		$	186		$	954		$	1,140		$	898
	Gross amounts offset in the consolidated balance sheets		(22		)		(6		)	(28		)	(22		)	(6		)	(28		)	—
	Cash collateral posted1		—				—			—			(38		)	(9		)	(47		)	(47		)
	Net amounts presented in the consolidated balance sheets		$	129			$	85		$	214		$	126		$	939		$	1,065		$	851
	1	In addition, at September 30, 2013 and December 31, 2012, SCE had posted $14 million and $8 million, respectively, of collateral that is not offset against the derivative liabilities and is reflected in "Other current assets" on the consolidated balance sheets.
	Income Statement Impact of Derivative Instruments
	SCE recognizes realized gains and losses on derivative instruments as purchased power expense and expects that such gains or losses will be part of the purchase power costs recovered from customers. As a result, realized gains and losses do not affect earnings, but may temporarily affect cash flows. Due to expected future recovery from customers, unrealized gains and losses are recorded as regulatory assets and liabilities and therefore also do not affect earnings. The results of derivative activities and related regulatory offsets are recorded in cash flows from operating activities in the consolidated statements of cash flows.
	The following table summarizes the components of SCE's economic hedging activity:
			Three months ended September 30,							Nine months ended
										September 30,
	(in millions)		2013				2012			2013			2012
	Realized losses		$	(15	)		$	(77	)	$	(38	)	$	(199	)
	Unrealized losses		(41		)		(91		)	(159		)	(29		)
	Notional Volumes of Derivative Instruments
	The following table summarizes the notional volumes of derivatives used for SCE hedging activities:
			Economic Hedges
	Commodity	Unit of Measure	September 30,			December 31, 2012
			2013
	Electricity options, swaps and forwards	GWh	8,964			15,884
	Natural gas options, swaps and forwards	Bcf	12			100
	Congestion revenue rights	GWh	127,772			149,774
	Tolling arrangements	GWh	97,893			101,485

Income_Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2013
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes
	Effective Tax Rate
	The table below provides a reconciliation of income tax expense computed at the federal statutory income tax rate to the income tax provision:
		Three months ended September 30,						Nine months ended
								September 30,
	(in millions)	2013			2012			2013			2012
	Edison International:
	Income from continuing operations before income taxes	$	665		$	610		$	863		$	1,204
	Provision for income tax at federal statutory rate of 35%	233			214			302			421
	Increase (decrease) in income tax from:
	State tax, net of federal benefit	22			46			5			60
	Property-related	(57		)	(20		)	(121		)	(39		)
	Uncertain tax positions	(5		)	1			13			2
	Other	(16		)	(13		)	(26		)	(23		)
	Total income tax expense from continuing operations	$	177		$	228		$	173		$	421
	Effective tax rate	26.6		%	37.4		%	20		%	35		%
	SCE:
	Income from continuing operations before income taxes	$	685		$	564		$	913		$	1,186
	Provision for income tax at federal statutory rate of 35%	240			197			319			415
	Increase (decrease) in income tax from:
	State tax, net of federal benefit	21			10			12			30
	Property-related	(57		)	(19		)	(121		)	(39		)
	Uncertain tax positions	(6		)	1			11			1
	Other	(15		)	(13		)	(25		)	(23		)
	Total income tax expense from continuing operations	$	183		$	176		$	196		$	384
	Effective tax rate	26.7		%	31.2		%	21.5		%	32.4		%
	The CPUC requires flow-through ratemaking treatment for the current tax benefit arising from certain property-related and other temporary differences which reverse over time. The accounting treatment for these temporary differences results in recording regulatory assets and liabilities for amounts that would otherwise be recorded to deferred income tax expense.
	Property-related items include recognition of income tax benefits from repair deductions for income tax purposes.
	Tax Disputes
	Edison International's federal income tax returns and its California combined franchise tax returns are currently open for years subsequent to 2002. In addition, specific California refund claims made by Edison International for years 1991 through 2002 are currently under review by the Franchise Tax Board.
	Tax Years 2003 – 2006
	The IRS examination phase of tax years 2003 through 2006 was completed in the fourth quarter of 2010, which included proposed adjustments for the following two items:
	•	A proposed adjustment increasing the taxable gain on the 2004 sale of EME's international assets, which if sustained, would result in a federal tax payment of approximately $205 million, including interest and penalties through September 30, 2013 (the IRS has asserted a 40% penalty for understatement of tax liability related to this matter).
	•	A proposed adjustment to disallow a component of SCE's repair allowance deduction, which if sustained, would result in a federal tax payment of approximately $99 million, including interest through September 30, 2013.
	Edison International disagrees with the proposed adjustments and filed a protest with the IRS in the first quarter of 2011. The appeals process to date has not resulted in a change in the proposed adjustment by the IRS on the taxable gain on the 2004 sale of EME's international assets. If a deficiency notice is issued on this item, it would require payment of the tax, interest and any penalties within 90 days of its issuance or a filing of a petition in United States Tax Court.
	Tax Years 2007 – 2009
	The IRS examination phase of tax years 2007 through 2009 was completed during the first quarter of 2013. Edison International received a Revenue Agent Report from the IRS on February 28, 2013 which included a proposed adjustment to disallow a component of SCE's repair allowance deduction (similar to the 2003 – 2006 tax years). The proposed adjustment to disallow a component of SCE's repair allowance deduction, if sustained, would result in a federal tax payment of approximately $74 million, including interest through September 30, 2013. Edison International disagrees with the proposed adjustment and filed a protest with the IRS in April 2013.
	Net Operating Loss and Tax Credit Carryforwards
	Edison International recently completed filing its 2012 tax returns. As adjusted for the amounts reflected in these tax returns, Edison International had $311 million of federal tax credit carryforwards of which $289 million expire between 2029 and 2032 and the remainder has no expiration date. In addition, as adjusted for the amounts reflected in these tax returns there were $1.3 billion of net operating loss carryforwards (tax effected) of which $32 million expire between 2015 and 2024, and the remainder expire in 2031 and 2032.
	As adjusted for the amounts reflected in these tax returns, SCE had $44 million of federal tax credit carryforwards of which $30 million expire between 2030 and 2032 and the remainder has no expiration date. In addition, as adjusted for the amounts reflected in these tax returns, there were $177 million of net operating loss carryforwards (tax effected) of which $18 million expire between 2015 and 2016, and the remainder expires in 2031 and 2032.
	Edison International has recorded deferred tax assets related to net operating losses and tax credit carryforwards that pertain to Edison International's consolidated or combined federal and state tax returns. Edison International continues to consolidate EME for federal and certain combined state tax returns. Under federal and state tax regulations, a tax deconsolidation of EME in future periods, as expected through the bankruptcy proceeding would reduce the amounts that Edison International would be eligible to use in future periods. As a result of the expected future tax deconsolidation and separation of EME from Edison International, Edison International has recorded a valuation allowance based on the estimated amount of such benefits as calculated under the applicable federal and state tax regulations. During the third quarter of 2013, Edison International revised its estimate of the tax impact of net operating losses and valuation allowance based on completion of the 2012 tax returns, as well as the estimated impact during 2013, which resulted in a $25 million tax provision (recorded as part of discontinued operations). The tax impact related to completion of the 2012 tax returns resulted from lower net operating losses from EME and an increase in the amount of projected net operating loss retained by EME upon deconsolidation and separation from Edison International. Changes in the amount of tax attributes may impact the amount of the valuation allowance and thereby affect income or losses from discontinued operations (see Note 16).

Compensation_and_Benefit_Plans

Compensation and Benefit Plans	9 Months Ended
	Sep. 30, 2013
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]
Compensation and Benefit Plans	Compensation and Benefit Plans
	Pension Plans
	Edison International made contributions of $175 million during the nine months ended September 30, 2013, which includes contributions of $163 million by SCE. Edison International expects to make contributions of $13 million during the remainder of 2013, which includes $2 million from SCE. Annual contributions made to most of SCE's pension plans are anticipated to be recovered through CPUC-approved regulatory mechanisms. Annual contributions to these plans are expected to be, at a minimum, equal to the related annual expense.
	Expense components for continuing operations are:
		Three months ended September 30,							Nine months ended
									September 30,
	(in millions)	2013				2012			2013			2012
	Edison International:
	Service cost	$	38			$	44		$	114		$	121
	Interest cost	42				46			126			137
	Expected return on plan assets	(58		)		(53		)	(172		)	(164		)
	Settlement costs1	24				1			73			4
	Amortization of prior service cost	1				1			3			3
	Amortization of net loss2	15				18			45			48
	Expense under accounting standards	$	62			$	57		$	189		$	149
	Regulatory adjustment (deferred)	(7		)		(57		)	(21		)	(3		)
	Total expense recognized	$	55			$	—		$	168		$	146
	SCE:
	Service cost	$	37			$	46		$	111		$	120
	Interest cost	41				45			123			135
	Expected return on plan assets	(57		)		(52		)	(171		)	(162		)
	Settlement costs	24				1			72			3
	Amortization of prior service cost	1				1			3			3
	Amortization of net loss2	14				14			42			42
	Expense under accounting standards	$	60			$	55		$	180		$	141
	Regulatory adjustment (deferred)	(7		)		(57		)	(21		)	(3		)
	Total expense recognized	$	53			$	(2	)	$	159		$	138
	1	Includes the amount of net loss reclassified from other comprehensive loss. The amount reclassified for Edison International was $2 million for the nine months ended September 30, 2013.
	2	Includes the amount of net loss reclassified from other comprehensive loss. The amount reclassified for Edison International and SCE was $4 million and $3 million for the three months ended September 30, 2013, respectively, and $11 million and $8 million for the nine months ended September 30, 2013, respectively.
	Under generally accepted accounting principles (“GAAP”), a settlement is recorded when lump-sum payments exceed estimated annual service and interest costs. As of May 31, 2013 and August 31, 2013, lump-sum payments to employees retiring in 2013 from the SCE Retirement Plan (primarily due to workforce reductions described below) exceeded the estimated service and interest costs for the year. A settlement requires re-measurement of both the plan pension obligations and plan assets as of the date of the settlement. The re-measurement of the SCE Retirement Plan as of May 31, 2013 and August 31, 2013 resulted in total actuarial gains of $338 million, including $341 million for SCE. The actuarial gains are primarily due to an increase in the discount rate (from 3.75% at December 31, 2012 to 4.25% as of May 31, 2013 and 4.50% as of August 31, 2013) due to higher interest rates and performance of the plan assets.
	After re-measurement, GAAP requires an acceleration of a portion of unrecognized net losses attributable to such lump-sum payments as additional pension expense as reflected in the above table. The additional pension expense related to SCE did not impact net income as such amounts are probable of recovery through future rates.
	The projected benefit obligations exceeded the fair value of the SCE Retirement Plan assets by $739 million, including $701 million for SCE, at August 31, 2013 compared to $1.11 billion, including $1.07 billion for SCE, at December 31, 2012.
	Postretirement Benefits Other Than Pensions
	Edison International made contributions of $22 million during the nine months ended September 30, 2013 and expects to make contributions of $13 million during the remainder of 2013, all of which are expected to be made by SCE. Annual contributions made to SCE plans are anticipated to be recovered through CPUC-approved regulatory mechanisms and are expected to be, at a minimum, equal to the total annual expense for these plans. Benefits under these plans, with some exceptions, are generally unvested and subject to change.
	Expense components for continuing operations are:
		Three months ended September 30,							Nine months ended
									September 30,
	(in millions)	2013				2012			2013			2012
	Edison International:
	Service cost	$	14			$	13		$	42		$	37
	Interest cost	26				28			78			85
	Expected return on plan assets	(30		)		(27		)	(90		)	(81		)
	Special termination benefits1	—				3			10			3
	Amortization of prior service credit	(9		)		(9		)	(27		)	(27		)
	Amortization of net loss2	7				12			21			35
	Total expense	$	8			$	20		$	34		$	52
	SCE:
	Service cost	$	14			$	12		$	41		$	36
	Interest cost	26				28			78			84
	Expected return on plan assets	(30		)		(27		)	(90		)	(81		)
	Special termination benefits1	—				3			10			3
	Amortization of prior service credit	(9		)		(9		)	(27		)	(27		)
	Amortization of net loss2	7				11			21			33
	Total expense	$	8			$	18		$	33		$	48
	1	Due to the reduction in workforce, SCE has incurred costs for extended retiree health care coverage.
	2	Includes the amount of net loss reclassified from other comprehensive loss. The amount reclassified for Edison International and SCE was less than $1 million and zero for the three- and nine-months ended September 30, 2013, respectively.
	Workforce Reductions
	In 2012, SCE commenced multiple efforts to reduce its workforce, which were largely completed by the end of the second quarter of 2013, in order to reflect SCE's strategic direction to optimize its cost structure, moderate customer rate increases and align its cost structure with its peers. In addition, in June 2013, SCE announced plans to permanently retire San Onofre. This announcement will result in a further reduction of the San Onofre workforce by approximately 960 employees and support organizations by approximately 175 employees. The majority of such reductions occurred in 2013. See Note 9 for further details. The following table provides a summary of changes in the accrued severance liability associated with these reductions:
	(in millions)
	Balance at January 1, 2013		$	104
	Additions		109
	Payments		(132		)
	Balance at September 30, 2013		$	81
	The liability presented in the table above is reflected in "Other current liabilities" on the consolidated balance sheets. The severance costs are included in "Operation and maintenance" on the consolidated income statements.

Permanent_Retirement_of_San_On

Permanent Retirement of San Onofre (Notes)	9 Months Ended
	Sep. 30, 2013
Retirement of Plant [Abstract]
Permanent Retirement of San Onofre	Permanent Retirement of San Onofre
	Tube Leak and Response
	Replacement steam generators were installed at San Onofre in 2010 and 2011. In the first quarter of 2012, a water leak suddenly occurred in one of the heat transfer tubes in San Onofre's Unit 3 steam generators. The Unit was safely taken off-line and subsequent inspections revealed excessive tube to tube wear. At the time, Unit 2 was off-line for a planned outage when areas of unexpected tube to support structure wear were found. Both Units have remained shut down since early 2012 and have undergone extensive inspections, testing and analysis following discovery of the leak. In October 2012, SCE submitted a restart plan to the Nuclear Regulatory Commission (“NRC”).
	Permanent Retirement
	On June 6, 2013 SCE decided to permanently retire Units 2 and 3. SCE concluded that despite the NRC's extensive review of SCE's restart plan for Unit 2 since October 2012, there still remained considerable uncertainty about when the review process would be concluded. Given the considerable uncertainty of when or whether SCE would be permitted to restart Unit 2, SCE concluded that it was in the best interest of its customers, shareholders and other stakeholders to permanently retire the Units and focus on planning for the replacement resources which will eventually be required for grid reliability. SCE also concluded that its decision to retire the Units would facilitate more orderly planning for California's energy future without the uncertainty of whether, when or how long San Onofre would continue to operate.
	CPUC Review
	In October 2012 the CPUC issued an Order Instituting Investigation (“OII”) that consolidated all San Onofre issues in related regulatory proceedings to consider appropriate cost recovery for all San Onofre costs, including among other costs, the cost of the steam generator replacement project, substitute market power costs, capital expenditures, operation and maintenance costs, and seismic study costs. The OII requires that all San Onofre-related costs incurred on and after January 1, 2012 be tracked in a memorandum account and, to the extent collected in rate levels authorized in the 2012 GRC or other proceeding, be subject to refund. The Order also states that the CPUC will determine whether to order the immediate removal, effective as of the date of the OII, of costs and rate base related to San Onofre from SCE's rates. Various other parties have filed testimony in the OII asking for disallowance of some or all of the San Onofre-related costs, including costs in excess of the amount impaired by SCE.
	A summary of financial items related to San Onofre and implicated in the OII are as follows:
	•	Approximately $1.1 billion of SCE's authorized revenue requirement collected since January 1, 2012 (subject to refund) associated with operating and maintenance expenses, depreciation, taxes and return on SCE's investment in Unit 2, Unit 3 and common plant. In June 2013, SCE recorded approximately $56 million in severance costs associated with its decision to retire both Units. Until funding of post June 6, 2013 activities related to the permanent closure of the plant is transitioned from base rates to SCE's nuclear decommissioning trusts set up for that purpose, SCE will continue to record these costs through the San Onofre OII memorandum account, subject to reasonableness review.
	•	At May 31, 2013, SCE's net investment associated with San Onofre was $2.1 billion, including net book value of remaining property, plant and equipment, construction work-in-progress, nuclear fuel inventory and materials and supplies.
	•	In 2005, the CPUC authorized expenditures of approximately $525 million ($665 million based on SCE's estimate after adjustment for inflation using the Handy-Whitman Index) for SCE's 78.21% share of the costs to purchase and install the four new steam generators in Units 2 and 3 and remove and dispose of their predecessors. SCE has spent $602 million on the steam generator replacement project, not including inspection, testing and repair costs subsequent to the replacement steam generator leak in Unit 3.
	•	As a result of outages associated with the steam generator inspection and repair, electric power and capacity normally provided by San Onofre were purchased in the market by SCE. These market power costs will be reviewed as part of the CPUC's OII proceeding. Estimated market power costs calculated in accordance with the OII methodology were approximately $680 million as of June 6, 2013, excluding avoided nuclear fuel costs which are no longer included as a reduction due to SCE's decision to permanently retire Units 2 and 3. Such amount includes costs of approximately $65 million associated with planned outage periods. SCE believes that such costs should be excluded as they would have been incurred even had the replacement steam generators performed as expected. Estimated market power costs calculated in accordance with the OII methodology from June 7, 2013 through September 30, 2013 was approximately $191 million. The CPUC will ultimately determine a final methodology for estimating market power costs as it continues its review of the issues in the OII.
	•	Through September 30, 2013, SCE's share of incremental inspection and repair costs totaled $115 million for both Units (not including payments made by MHI as described below). SCE recorded its share of payments made to date by MHI ($36 million) as a reduction of incremental inspection and repair costs in 2012.
	SCE believes that the actions taken and costs incurred in connection with the San Onofre replacement steam generators, outages and permanent retirement have been prudent. Nevertheless, SCE cannot provide assurance that the CPUC will not disallow costs incurred or order refunds to customers of amounts collected in rates or that SCE will be successful in recovering amounts from third parties. Disallowances of costs and/or refund of amounts received from customers could be material and adversely affect SCE's financial condition, results of operations and cash flows.
	Accounting for Early Retirement of San Onofre Units 2 and 3
	As a result of the decision to early retire San Onofre Units 2 and 3, GAAP requires reclassification of the amounts recorded in property, plant and equipment and related tangible operating assets to a regulatory asset to the extent that management concludes it is probable of recovery through future rates. Regulatory assets may also be recorded to the extent management concludes it is probable that direct and indirect costs incurred to retire Units 2 and 3 as of each reporting date are recoverable through future rates. These costs may include, but are not limited to, severance benefits to reduce the workforce at San Onofre to the staffing required to safely store and secure the plant prior to conducting decommissioning activities, losses on termination of purchase contracts, including nuclear fuel, and losses on disposition of excess inventory. GAAP also requires recognition of a liability to the extent management concludes it is probable SCE will be required to refund amounts from authorized revenues previously collected from customers.
	In assessing whether to record regulatory assets as a result of the decision to retire San Onofre Units 2 and 3 early and whether to record liabilities for refunds to customers, SCE considered the interrelationship of recovery of costs and refunds to customers for accounting purposes, as such matters are being considered by the CPUC on a consolidated basis in the San Onofre OII. SCE also considered that it will continue to use certain portions of the plant (such as fuel storage, security facilities and buildings) as part of ongoing activities at the site. SCE additionally reviewed relevant regulatory precedents and statutory provisions regarding the regulatory recovery of early retired assets previously placed in service and related materials, supplies and fuel. Such precedents have generally permitted cost recovery of the remaining net investment in early retired assets, absent a finding of imprudency. Such precedents vary on whether a full, partial or no rate of return is allowed on the investment in such assets, but generally provide accelerated recovery when less than a full return is authorized. Furthermore, once the Units are removed from rate base, under normal principles of cost of service ratemaking and relevant statutory provisions, SCE should, absent imprudence, recover the costs it incurs to purchase power that might otherwise have been produced by San Onofre. SCE continues to believe that the actions it has taken and the costs it has incurred in connection with the San Onofre replacement steam generators and outages have been prudent.
	As a result of such considerations, SCE considered a number of potential outcomes for the matters being considered by the CPUC in the San Onofre OII, none of which are assured, but a number of which in SCE's opinion appeared to be more likely than a number of other outcomes. SCE considered the likelihood of outcomes to determine the amount deemed probable of recovery. These outcomes included a number of variables, including recovery of and return on the components of SCE's net investment, and the potential for refunds to customers for either substitute power or operating costs occurring over different time periods. SCE also included in its consideration of possible outcomes, the requirement under GAAP to discount future cash flows from recovery of assets without a return at its incremental borrowing rate.
	As a result of the foregoing assessment, SCE:
	•	Reclassified $1,521 million of its total investment in San Onofre at May 31, 2013 as described above to a regulatory asset (“San Onofre Regulatory Asset”). Included in the San Onofre Regulatory Asset is approximately $404 million of property, plant and equipment, including construction work in progress that is expected to support ongoing activities at the site. In addition, to the extent the San Onofre Regulatory Asset includes excess nuclear fuel and material and supplies, SCE will, if possible, sell such excess amounts to third parties and reduce the amount of the regulatory asset by such proceeds.
	•	Recorded an impairment charge of $575 million ($365 million after tax) in the second quarter of 2013.
	As part of the decision to permanently retire the Units at San Onofre, SCE announced a workforce reduction of approximately 960 employees and accrued additional severance costs of $56 million (SCE's share) based on its conclusion that it is probable, though not certain, that such costs will be recovered in future rates. The estimate for these costs was previously included in SCE's estimate to decommission the units. After acceptance of the decommissioning plan by the NRC, SCE expects a further workforce reduction of approximately 175 employees.
	As of September 30, 2013, SCE recorded a net regulatory asset of $1.45 billion comprised of: $1.54 billion of property, plant and equipment; $33 million estimated losses on disposition of nuclear fuel inventory; less $129 million for estimated refunds of authorized revenue recorded in excess of SCE’s costs of service, including a return on capital through June 6, 2013. SCE's judgment that the San Onofre Regulatory Asset recorded at September 30, 2013 is probable, though not certain, of recovery is based on SCE's knowledge of the facts and judgment in applying relevant regulatory principles to the issues under review in the OII proceeding and in accordance with GAAP. Such judgment is subject to considerable uncertainty, and regulatory principles and precedents are not necessarily binding and are capable of interpretation. No decisions have been rendered in the OII proceeding regarding recoverability of costs from future rates or refunds of amounts to customers. The CPUC may or may not agree with SCE, after review of all of the facts and circumstances, and SCE may advocate positions that it believes are supported by relevant precedent and regulatory principles that are more favorable to SCE than the charges it has recorded in accordance with GAAP. The CPUC could also conclude that SCE acted imprudently regarding the San Onofre replacement steam generator project, including its response to the outage that commenced at the end of January 2012. Thus, there can be no assurance that the OII proceeding will provide for recoveries as estimated by SCE, including the recovery of costs recorded as a regulatory asset, or that the CPUC does not order refunds to customers from amounts that were previously authorized as subject to refund. Accordingly, the amount recorded for the San Onofre Regulatory Asset at September 30, 2013, is subject to change based upon future developments and the application of SCE's judgment to those events.
	Third-Party Recovery
	The replacement steam generators were designed and supplied by MHI and are warranted for an initial period of 20 years from acceptance. MHI is contractually obligated to repair or replace defective items with dispatch and to pay specified damages for certain repairs. MHI's liability under the purchase agreement is limited to $138 million and excludes consequential damages, defined to include "the cost of replacement power;" however, limitations in the contract are subject to applicable exceptions both in the contract and under law. SCE has advised MHI that it believes one or more of such exceptions apply and MHI's liability is not limited to $138 million, and MHI has advised SCE that it disagrees. In October 2013, after a prescribed 90-day waiting period from the service of an earlier notice of dispute, SCE sent MHI a formal request for binding arbitration under the auspices of the International Chamber of Commerce in accordance with the purchase contract seeking damages for all losses. In the request for arbitration, SCE alleges that MHI totally and fundamentally failed to deliver what it promised, and that the contractual limitations of liability are subject to applicable exceptions in the contract and under law. Each of the other co-owners filed lawsuits against MHI, alleging claims arising from MHI's supplying the faulty steam generators. MHI has requested that these lawsuits be stayed pending the arbitration with SCE.
	SCE, on behalf of itself and the other San Onofre co-owners, has submitted seven invoices to MHI totaling $149 million for steam generator repair costs incurred through April 30, 2013. MHI paid the first invoice of $45 million, while reserving its right to challenge any of the charges in the invoice. In January 2013, MHI advised SCE that it rejected a portion of the first invoice and required further documentation regarding the remainder of the invoice. In September 2013, SCE reiterated its request to MHI for payment of outstanding invoices. SCE has recorded its share of the invoice paid as a reduction of repair and inspection costs.
	San Onofre carries both accidental property damage and accidental outage insurance issued by Nuclear Electric Insurance Limited (“NEIL”) and has placed NEIL on notice of claims under both policies. The NEIL policies have a number of exclusions and limitations that may reduce or eliminate coverage. The estimated total claims under the accidental outage insurance through June 30, 2013 are approximately $390 million (SCE’s share of which is approximately $306 million). Pursuant to these proofs of loss, SCE is seeking the weekly indemnity amounts provided under the accidental outage policy for each Unit. Accidental outage policy benefits are reduced by 90% for the periods following announcement of the permanent retirement of the Units. SCE has not submitted a proof of loss under the accidental property damage insurance. No amounts have been recognized in SCE's financial statements, pending NEIL's response. SCE's current expectation is that NEIL will make a coverage determination by the end of the first quarter of 2014.
	Continuing NRC Proceedings
	As part of the NRC's review of the San Onofre outage and proceedings related to the possible restart of Unit 2, the NRC appointed an Augmented Inspection Team to review SCE's performance. In September 2013, the NRC issued an Inspection Report in connection with The Augmented Inspection Team’s review and SCE’s response to an earlier NRC Confirmatory Action Letter. The NRC’s report contained a preliminary “white” finding (low to moderate safety significance) and an apparent violation regarding the steam generators in Unit 3 and a preliminary “green” finding (very low safety significance) for Unit 2’s steam generators for failing to ensure that MHI’s modeling and analysis were adequate. Simultaneously, the NRC issued an Inspection Report to MHI containing a Notice of Nonconformance for its flawed computer modeling in the design of San Onofre’s steam generators. In October 2013, SCE submitted comments to the NRC on the characterizations contained in the Inspection Report but did not contest the findings or violation. In addition, the NRC's Office of Investigations has been conducting an investigation into the accuracy and completeness of information SCE provided to the Augmented Inspection Team. SCE has also been made aware of an investigation related to San Onofre by the NRC's Office of Inspector General, which generally reviews internal NRC affairs. Certain anti-nuclear groups and individual members of Congress have alleged that SCE knew of deficiencies in the steam generators when they were installed or otherwise did not correctly follow NRC requirements in connection with the design and installation of the replacement steam generators, something which SCE has vigorously denied, and have called for investigations, including by the Department of Justice. SCE cannot predict when or whether ongoing inquiries or investigations by the NRC will be completed or whether inquiries by other government agencies will be initiated. Should the NRC find a deficiency in SCE's provision of information, SCE could be subject to additional NRC actions, including the imposition of penalties, and the findings could be taken into consideration in the CPUC regulatory proceedings described above.

Other_Investments

Other Investments	9 Months Ended
	Sep. 30, 2013
Regulated Entity, Other Assets, Noncurrent [Abstract]
Other Investments	Other Investments
	Nuclear Decommissioning Trusts
	Future decommissioning costs of removal of SCE's nuclear assets are expected to be funded from independent decommissioning trusts, which currently receive contributions of approximately $23 million per year through SCE customer rates.
	The following table sets forth amortized cost and fair value of the trust investments:
		Longest		Amortized Cost								Fair Value
		Maturity
	(in millions)	Dates		September 30,				December 31,				September 30,				December 31, 2012
				2013				2012				2013
	Stocks	—		$	635			$	978			$	2,027			$	2,271
	Municipal bonds	2051		701				518				796				644
	U.S. government and agency securities	2043		861				547				924				603
	Corporate bonds	2054		176				324				221				410
	Short-term investments, primarily cash equivalents	One-year		351				117				367				121
	Total investments			2,724				2,484				4,335				4,049
	Net payables			(3		)		(1		)		(3		)		(1		)
	Total nuclear decommissioning trusts			$	2,721			$	2,483			$	4,332			$	4,048
	Trust fund earnings (based on specific identification) increase the trust fund balance and the ARO regulatory liability. Proceeds from sales of securities (which are reinvested) were $2.6 billion and $428 million for the three months ended September 30, 2013 and 2012, respectively and $4.6 billion and $1.5 billion for the nine months ended September 30, 2013 and 2012, respectively. Unrealized holding gains, net of losses, were $1.6 billion at both September 30, 2013 and December 31, 2012.
	The following table sets forth a summary of changes in the fair value of the trust:
		Three months ended September 30,								Nine months ended
										September 30,
	(in millions)	2013				2012				2013				2012
	Balance at beginning of period	$	4,182			$	3,810			$	4,048			$	3,592
	Gross realized gains	119				13				261				54
	Gross realized losses	(17		)		—				(18		)		(5		)
	Unrealized gains, net	55				156				46				272
	Other-than-temporary impairments	(15		)		(7		)		(44		)		(30		)
	Interest, dividends, contributions and other	8				25				39				114
	Balance at end of period	$	4,332			$	3,997			$	4,332			$	3,997
	Due to regulatory mechanisms, earnings (including other-than-temporary impairments) and realized gains and losses have no impact on operating revenue or earnings.

Regulatory_Assets_and_Liabilit

Regulatory Assets and Liabilities	9 Months Ended
	Sep. 30, 2013
Regulatory Assets and Liabilities Disclosure [Abstract]
Regulatory Assets and Liabilities	Regulatory Assets and Liabilities
	As a result of the permanent retirement of San Onofre, SCE's net regulatory asset as of September 30, 2013 was $1.45 billion comprised of: $1.54 billion of property, plant and equipment; $33 million estimated losses on disposition of nuclear fuel inventory (see Note 12 for further information); less $129 million of authorized revenue from the 2012 GRC in excess of revenues recognized based on costs incurred and a return on capital through June 6, 2013, pending the outcome of the regulatory proceedings.
	Regulatory Assets
	Regulatory assets included on the consolidated balance sheets are:
	(in millions)	September 30,		December 31,
		2013		2012
	Current:
	Regulatory balancing accounts	$	344	$	502
	Energy derivatives	162		70
	Total current	506		572
	Long-term:
	Deferred income taxes, net	2,911		2,663
	Pensions and other postretirement benefits	1,105		1,550
	Energy derivatives	960		900
	Unamortized investments, net	358		507
	San Onofre	1,450		—
	Unamortized loss on reacquired debt	213		228
	Nuclear-related investment, net	34		141
	Regulatory balancing accounts	626		73
	Other	358		360
	Total long-term	8,015		6,422
	Total regulatory assets	$	8,521	$	6,994
	Regulatory Liabilities
	Regulatory liabilities included on the consolidated balance sheets are:
	(in millions)	September 30,		December 31,
		2013		2012
	Current:
	Regulatory balancing accounts	$	580	$	484
	Other	49		52
	Total current	629		536
	Long-term:
	Costs of removal	2,814		2,731
	Asset retirement obligations	954		1,385
	Regulatory balancing accounts	1,210		1,091
	Other	11		7
	Total long-term	4,989		5,214
	Total regulatory liabilities	$	5,618	$	5,750
	The regulatory liability related to asset retirement obligations represents the nuclear decommissioning trust assets in excess of the related asset retirement obligations. The decrease in this regulatory liability resulted from a revision to the asset retirement obligations of San Onofre. For further information, see Note 1.

Commitments_and_Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2013
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies
	Third-Party Power Purchase Agreements
	During the nine months ended September 30, 2013, SCE had new power purchase contracts classified as operating leases. The additional commitments are estimated to be: $247 million for 2014, $340 million in 2015, $413 million in 2016, $415 million in 2017 and $4.43 billion for the period remaining thereafter.
	Other Commitments
	As of December 31, 2012, SCE had nuclear fuel supply commitments of $912 million for the 2013 – 2017 period and thereafter. As a result of the decision to permanently retire San Onofre Units 2 and 3, SCE has submitted fuel contract delivery cancellation notices for these contractual arrangements. As of September 30, 2013, SCE had accrued a liability of $33 million related to estimated costs associated with the cancellation and management of future deliveries of nuclear fuel and recorded a regulatory asset for recovery of costs in the future. See Note 9 for further discussion of SCE's decision to permanently retire San Onofre.
	Indemnities
	Edison International and SCE have various financial and performance guarantees and indemnity agreements which are issued in the normal course of business. The contracts discussed below included performance guarantees.
	Indemnity Provided as Part of the Acquisition of Mountainview
	In connection with the acquisition of the Mountainview power plant, SCE agreed to indemnify the seller with respect to specific environmental claims related to SCE's previously owned San Bernardino Generating Station, divested by SCE in 1998 and reacquired in 2004 as part of the Mountainview acquisition. SCE retained certain responsibilities with respect to environmental claims as part of the original divestiture of the station. The aggregate liability for either party to the purchase agreement for damages and other amounts is a maximum of $60 million. This indemnification for environmental liabilities expires on or before March 12, 2033. SCE has not recorded a liability related to this indemnity.
	Mountainview Filter Cake Indemnity
	SCE has indemnified the City of Redlands, California in connection with Mountainview's California Energy Commission permit for cleanup or associated actions related to groundwater contaminated by perchlorate due to the disposal of filter cake at the City's solid waste landfill. The obligations under this agreement are not limited to a specific time period or subject to a maximum liability. SCE has not recorded a liability related to this indemnity.
	Other Indemnities
	Edison International and SCE provide other indemnifications through contracts entered into in the normal course of business. These are primarily indemnifications against adverse litigation outcomes in connection with underwriting agreements, and indemnities for specified environmental liabilities and income taxes with respect to assets sold. Edison International's and SCE's obligations under these agreements may or may not be limited in terms of time and/or amount, and in some instances Edison International and SCE may have recourse against third parties. Edison International and SCE have not recorded a liability related to these indemnities. The overall maximum amount of the obligations under these indemnifications cannot be reasonably estimated.
	Contingencies
	In addition to the matters disclosed in these Notes, Edison International and SCE are involved in other legal, tax and regulatory proceedings before various courts and governmental agencies regarding matters arising in the ordinary course of business. Edison International and SCE believe the outcome of these other proceedings will not, individually or in the aggregate, materially affect its results of operations or liquidity.
	San Onofre
	SCE believes that the actions taken and costs incurred in connection with the San Onofre replacement steam generators and outages have been prudent. Accordingly, SCE considers its operating, capital, and market power costs, recoverable through base rates and the ERRA balancing account, as offset by third-party recoveries where applicable. SCE cannot provide assurance that the CPUC will not disallow costs incurred or order refunds to customers of amounts collected in rates, or that SCE will be successful in recovering amounts from third parties. Disallowances of costs and/or refund of amounts received from customers could be material and adversely affect SCE's financial condition, results of operations and cash flows. SCE will pursue recoveries arising from available agreements, but there is no assurance that SCE will recover all of its applicable costs pursuant to these arrangements. See Note 9 for further details.
	EME Chapter 11 Bankruptcy Filing
	On December 17, 2012 (the "Petition Date"), EME and certain of its wholly-owned subsidiaries filed voluntary petitions for relief under Chapter 11 of the United States Bankruptcy Code in the United States Bankruptcy Court for the Northern District of Illinois, Eastern Division ("Bankruptcy Court") (see Note 16 for further details). Under the Transaction Support Agreement (the "Support Agreement") to which EME, Edison International and certain of EME's senior unsecured noteholders ("Consenting Noteholders") were parties, each of them had agreed to support Bankruptcy Court approval of the Settlement Transaction. EME was required to seek authority from the Bankruptcy Court to enter into the Settlement Transaction by the deadline set out in the Support Agreement and did not do so. EME's failure to meet this deadline rendered the Support Agreement terminable by Edison International or the Consenting Noteholders at any time, and on July 25, 2013, a requisite majority of the Consenting Noteholders provided Edison International and EME with a notice terminating the Support Agreement, effective August 1, 2013. As a result, the extension of the Tax Allocation Agreement contemplated by the Support Agreement has also terminated, and the Tax Allocation Agreement is now due to expire by its terms on December 31, 2013. Furthermore, claims, which Edison International submitted in the EME bankruptcy on a contingency basis, will not be released, and inasmuch as Edison International will not be entitled to the benefits of the Settlement Transaction, it will remain subject to any claims of EME and potentially its creditors, including claims relating to or arising out of any shared services, the Tax Allocation Agreement, and any other relationships or transactions between the companies.
	On August 1, 2013, the Official Committee of Unsecured Creditors made a motion in the Bankruptcy Court to seek sole authority to file, prosecute and settle alleged claims against Edison International, SCE, certain other subsidiaries of Edison International, and present and former directors of Edison International, SCE and EME. Such motion has not been acted upon by the Bankruptcy Court but was supported by the Consenting Noteholders and was accompanied by a proposed complaint, which has not been filed or served. The motion was opposed by EME, and although EME indicated that immediate litigation was not in EME’s interest, EME indicated that it had been preparing a similar complaint and would file it were it to conclude that it would be in EME’s best interests to do so. The proposed complaint sets forth a variety of theories to allege damages against the named defendants, including, among other things, that $925 million in dividends paid by EME to Mission Energy Holding Company in 2007 are recoverable, that $183 million paid by EME under the Tax Allocation Agreement in September 2012 was not proper, that EME was operated between 2010 and 2012 for Edison International’s benefit and not in accordance with fiduciary duties owed to EME and its creditors, that the amendment of the Tax Allocation Agreement to have it expire December 31, 2013 in the absence of a settlement was a breach of fiduciary duty, that Edison International overcharged EME for shared services, that Edison International and certain of its competitive subsidiaries are alter egos of and should be substantively consolidated with EME and therefore liable for EME’s debts, and that utilization by Edison International and SCE of bonus depreciation following EME’s filing for bankruptcy was a violation of the automatic stay in the EME bankruptcy. Edison International does not know if a complaint containing such allegations or other allegations will be filed and served, but it would vigorously contest such allegations.
	CPUC Safety and Enforcement Division Investigations
	San Gabriel Valley Windstorm Investigation
	In November 2011, a windstorm resulted in significant damage to SCE’s electric system and service outages for SCE customers primarily in the San Gabriel Valley. The CPUC directed its Safety and Enforcement Division (“SED”) to conduct an investigation focused on the cause of the outages, SCE’s service restoration effort, and SCE’s customer communications during the outages. The SED issued its final report on January 11, 2013. The report asserts that SCE and others with whom SCE shares utility poles violated certain CPUC safety rules applicable to overhead line construction, maintenance and operation, which may have caused the failures of affected poles and supporting cables. The report also concludes that SCE’s restoration time was not adequate and makes other assertions. Additionally, the report contends that SCE violated CPUC rules by failing to preserve evidence relevant to the investigation when it did not retain damaged poles that were replaced following the windstorm. If the CPUC issues an OII regarding this matter and SCE is found to have violated any CPUC rules, it could face penalties. SCE is unable to estimate a possible loss or range of loss associated with any penalties that may be imposed by the CPUC on SCE.
	Malibu Fire Order Instituting Investigation
	Following a 2007 wildfire in Malibu, California, the CPUC issued an OII to determine if any statutes, CPUC general orders, rules or regulations were violated by SCE or telecomm providers (“OII Respondents”) that shared the use of three failed power poles in the wildfire area. The SED alleged, among other things, that the poles were overloaded, that the OII Respondents violated the CPUC's rules governing the design, construction and inspection of poles, and that SCE failed to preserve evidence relevant to the investigation and misled the CPUC during its investigation of the fire. In May 2013, SCE and the SED agreed to the terms of a proposed settlement that would cause SCE to pay a total of $37 million, $17 million of which will be allocated to pole safety studies and remediation in the Malibu area and $20 million of which will be a penalty paid to the State General Fund. The settlement was approved by the CPUC in September 2013.
	Four Corners New Source Review Litigation
	In October 2011, four private environmental organizations filed a CAA citizen lawsuit against the co-owners of Four Corners. The complaint alleges that certain work performed at the Four Corners generating units 4 and 5, over the approximate periods of 1985 – 1986 and 2007 – 2010, constituted plant “major modifications” and the plant's failure to obtain permits and install best available control technology ("BACT") violated the PSD requirements and the New Source Performance Standards of the CAA. The complaint also alleges subsequent and continuing violations of BACT air emissions limits. The lawsuit seeks injunctive and declaratory relief, civil penalties, including a mitigation project and litigation costs. In November 2012, the parties requested a stay of the litigation to allow for settlement discussion, and the matter is currently stayed. In November 2010, SCE entered into an agreement to sell its ownership interest in generating units 4 and 5 to APS. The sale remains contingent upon APS obtaining a long-term fuel supply agreement for the plant. As of January 2013, the sale agreement became terminable by either party, but as of the date of this report, the agreement has not been terminated. The purchase price is subject to certain adjustments under the sale agreement, which includes a reduction in the purchase price of $7.5 million for each month between October 1, 2012 and the closing date. Under the agreement SCE would remain responsible for its pro-rata share of certain environmental liabilities, including penalties arising from environmental violations prior to the sale. SCE is unable to estimate a possible loss or range of loss associated with this matter.
	Environmental Remediation
	Edison International records its environmental remediation liabilities when site assessments and/or remedial actions are probable and a range of reasonably likely cleanup costs can be estimated. Edison International reviews its sites and measures the liability quarterly, by assessing a range of reasonably likely costs for each identified site using currently available information, including existing technology, presently enacted laws and regulations, experience gained at similar sites, and the probable level of involvement and financial condition of other potentially responsible parties. These estimates include costs for site investigations, remediation, operation and maintenance, monitoring and site closure. Unless there is a single probable amount, Edison International records the lower end of this reasonably likely range of costs (reflected in "Other long-term liabilities") at undiscounted amounts as timing of cash flows is uncertain.
	At September 30, 2013, Edison International's recorded estimated minimum liability to remediate its 19 identified material sites (sites in which the upper end of the range of the costs is at least $1 million) at SCE was $129 million, including $90 million related to San Onofre. In addition to its identified material sites, SCE also has 39 immaterial sites for which the total minimum recorded liability was $4 million. Of the $133 million total environmental remediation liability for SCE, $129 million has been recorded as a regulatory asset. SCE expects to recover $38 million through an incentive mechanism that allows SCE to recover 90% of its environmental remediation costs at certain sites (SCE may request to include additional sites) and $91 million through a mechanism that allows SCE to recover 100% of the costs incurred at certain sites through customer rates. Edison International's identified sites include several sites for which there is a lack of currently available information, including the nature and magnitude of contamination, and the extent, if any, that Edison International may be held responsible for contributing to any costs incurred for remediating these sites. Thus, no reasonable estimate of cleanup costs can be made for these sites.
	The ultimate costs to clean up Edison International's identified sites may vary from its recorded liability due to numerous uncertainties inherent in the estimation process, such as: the extent and nature of contamination; the scarcity of reliable data for identified sites; the varying costs of alternative cleanup methods; developments resulting from investigatory studies; the possibility of identifying additional sites; and the time periods over which site remediation is expected to occur. Edison International believes that, due to these uncertainties, it is reasonably possible that cleanup costs at the identified material sites and immaterial sites could exceed its recorded liability by up to $161 million and $7 million, respectively, all of which is related to SCE. The upper limit of this range of costs was estimated using assumptions least favorable to Edison International among a range of reasonably possible outcomes.
	SCE expects to clean up and mitigate its identified sites over a period of up to 30 years. Remediation costs for 2013 and in each of the next five years are expected to range from $6 million to $31 million. Costs incurred for the nine months ended September 30, 2013 and 2012 were $5 million for both respective periods.
	Based upon the CPUC's regulatory treatment of environmental remediation costs incurred at SCE, Edison International believes that costs ultimately recorded will not materially affect its results of operations, financial position or cash flows. There can be no assurance, however, that future developments, including additional information about existing sites or the identification of new sites, will not require material revisions to estimates.
	Nuclear Insurance
	Federal law limits public liability claims from a nuclear incident to the amount of available financial protection, which is currently approximately $13.6 billion. SCE and other owners of San Onofre and Palo Verde have purchased the maximum private primary insurance available ($375 million). The balance is covered by a loss sharing program among nuclear reactor licensees. If a nuclear incident at any licensed reactor in the United States results in claims and/or costs which exceed the primary insurance at that plant site, all nuclear reactor licensees could be required to contribute their share of the liability in the form of a deferred premium.
	Based on its ownership interests, SCE could be required to pay a maximum of approximately $255 million per nuclear incident. However, it would have to pay no more than approximately $38 million per incident in any one year. If the public liability limit above is insufficient, federal law contemplates that additional funds may be appropriated by Congress. This could include an additional assessment on all licensed reactor operators as a measure for raising further federal revenue.
	NEIL, a mutual insurance company owned by entities with nuclear facilities, issues primary property damage, decontamination and excess property damage and accidental outage insurance policies. At San Onofre and Palo Verde, property damage insurance covers losses up to $500 million, including decontamination costs. Decontamination liability and excess property damage coverage exceeding the primary $500 million also has been purchased in amounts greater than the federal requirement of a minimum of approximately $1.06 billion. Property damage insurance also covers damages caused by acts of terrorism up to specified limits. Additional outage insurance covers part of replacement power expenses during an accident-related nuclear unit outage.
	If losses at any nuclear facility covered by the arrangement were to exceed the accumulated funds for these insurance programs, SCE could be assessed retrospective premium adjustments of up to approximately $52 million per year. Insurance premiums are charged to operating expense.
	Wildfire Insurance
	Severe wildfires in California have given rise to large damage claims against California utilities for fire-related losses alleged to be the result of the failure of electric and other utility equipment. Invoking a California Court of Appeal decision, plaintiffs pursuing these claims have relied on the doctrine of inverse condemnation, which can impose strict liability (including liability for a claimant's attorneys' fees) for property damage. On September 1, 2013, Edison International, renewed its liability insurance coverage, which included coverage for SCE's wildfire liabilities up to a $500 million limit (with a self-insured retention of $10 million per wildfire occurrence). Various coverage limitations within the policies that make up this insurance coverage could result in additional self-insured costs in the event of multiple wildfire occurrences during the policy period (September 1, 2013 to May 31, 2014). SCE also has additional coverage for certain wildfire liabilities of $450 million, which applies when total covered wildfire claims exceed $550 million, through May 31, 2014. SCE may experience coverage reductions and/or increased insurance costs in future years. No assurance can be given that future losses will not exceed the limits of SCE's insurance coverage.
	Spent Nuclear Fuel
	Under federal law, the Department of Energy ("DOE") is responsible for the selection and construction of a facility for the permanent disposal of spent nuclear fuel and high-level radioactive waste. The DOE did not meet its contractual obligation to begin acceptance of spent nuclear fuel by January 31, 1998. Extended delays by the DOE have led to the construction of costly alternatives and associated siting and environmental issues. Currently, both San Onofre and Palo Verde have interim storage for spent nuclear fuel on site sufficient for the current license period.
	In June 2010, the United States Court of Federal Claims issued a decision granting SCE and the San Onofre co-owners damages of approximately $142 million to recover costs incurred through December 31, 2005 for the DOE's failure to meet its obligation to begin accepting spent nuclear fuel from San Onofre. SCE received payment from the federal government in the amount of the damage award in November 2011. SCE has returned to the San Onofre co-owners their respective share of the damage award paid. SCE, as operating agent, filed a lawsuit on behalf of the San Onofre owners against the DOE in the Court of Federal Claims in December 2011 seeking damages of approximately $98 million for the DOE's failure to meet its obligation to begin accepting spent nuclear fuel for the period from January 1, 2006 to December 31, 2010. Additional legal action would be necessary to recover damages incurred after December 31, 2010. All damages recovered by SCE are subject to CPUC review as to how these amounts would be distributed among customers, shareholders, or to offset fuel decommissioning or storage costs.

Preferred_and_Preference_Stock

Preferred and Preference Stock of Utility	9 Months Ended
	Sep. 30, 2013
Preferred And Preference Stock Of Utility Disclosure [Abstract]
Preferred and Preference Stock of Utility	Preferred and Preference Stock of Utility
	During the first quarter of 2013, SCE issued 160,004 shares of 5.10% Series G preference stock (cumulative, $2,500 liquidation value) to SCE Trust II, a special purpose entity formed to issue trust securities as discussed in Note 3. The Series G preference stock may be redeemed at par, in whole, but not in part, at any time prior to March 15, 2018 if certain changes in tax or investment company laws occur. After March 15, 2018, SCE may redeem the Series G shares at par, in whole or in part. The shares are not subject to mandatory redemption. The proceeds from the sale of these shares were used to redeem all outstanding shares of Series B and C preference stock.

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive Loss	9 Months Ended
	Sep. 30, 2013
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss
	Accumulated other comprehensive loss, net of tax, consists of:
		Pension and PBOP – Net Loss
	(in millions)	Three months ended September 30, 2013			Nine months ended September 30, 2013
	Edison International:
	Balance at beginning of period	$	(82	)	$	(87	)
	Other comprehensive loss before reclassifications	—			(2		)
	Amounts reclassified from accumulated other comprehensive loss1	3			10
	Net current-period other comprehensive loss	3			8
	Balance at end of period	$	(79	)	$	(79	)
	Reclassifications from accumulated other comprehensive loss:
	Amortization of net loss included in net income	$	4		$	13
	Tax expense	1			3
	Total reclassification, net of tax	$	3		$	10
	SCE:
	Balance at beginning of period	$	(30	)	$	(29	)
	Other comprehensive loss before reclassifications	—			(4		)
	Amounts reclassified from accumulated other comprehensive loss1	2			5
	Net current-period other comprehensive loss	2			1
	Balance at end of period	$	(28	)	$	(28	)
	Reclassifications from accumulated other comprehensive loss:
	Amortization of net loss included in net income	$	3		$	8
	Tax expense	1			3
	Total reclassification, net of tax	$	2		$	5
	1	These items are included in the computation of net periodic pension and PBOP expense. See Note 8 for additional information.

Interest_and_Other_Income_and_

Interest and Other Income and Expenses	9 Months Ended
	Sep. 30, 2013
Other Income and Expenses [Abstract]
Interest and Other Income and Expenses	Interest and Other Income and Other Expenses
	Interest and other income and expenses are as follows:
		Three months ended September 30,				Nine months ended
						September 30,
	(in millions)	2013		2012		2013		2012
	SCE interest and other income:
	Equity allowance for funds used during construction	$	14	$	23	$	54	$	71
	Increase in cash surrender value of life insurance policies	10		6		24		20
	Interest income	2		2		8		5
	Other	1		7		3		12
	Total SCE interest and other income	27		38		89		108
	Edison International Parent and Other income	1		—		2		2
	Total Edison International interest and other income	$	28	$	38	$	91	$	110
	SCE other expenses:
	Civic, political and related activities and donations	$	9	$	5	$	24	$	22
	Other	6		4		14		14
	Total SCE other expenses	15		9		38		36
	Edison International Parent and Other other expenses	—		1		—		—
	Total Edison International other expenses	$	15	$	10	$	38	$	36

Discontinued_Operations

Discontinued Operations	9 Months Ended
	Sep. 30, 2013
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	Discontinued Operations
	EME Chapter 11 Bankruptcy Filing
	EME and certain of its subsidiaries filed voluntary petitions for relief under Chapter 11 of the Bankruptcy Code in the Bankruptcy Court. See Note 12 for further details.
	Deconsolidation
	EME and those subsidiaries in Chapter 11 proceedings retain control of their assets and are authorized to operate their businesses as debtors-in-possession under the jurisdiction of the Bankruptcy Court. Effective December 17, 2012, Edison International no longer consolidates the earnings and losses of EME or its subsidiaries and has reflected its ownership interest in EME utilizing the cost method of accounting prospectively, under which Edison International's investment in EME is reflected as a single amount on the consolidated balance sheet of Edison International at December 31, 2012. Furthermore, Edison International has recorded a full impairment of the investment.
	Edison International will not be affected by changes in EME's future financial results, other than those changes related to certain tax matters. Edison International has evaluated the continuing cash flows with EME and determined that these cash flows generated are indirect and immaterial. Edison International's continuing cash flows will not include any significant revenue-producing and cost-generating activities of EME.
	Edison International considers EME to be an abandoned asset under generally accepted accounting principles, and, as a result, the operations of EME prior to December 17, 2012 and for all prior years are reflected as discontinued operations in the consolidated financial statements. Included in Edison International's consolidated income statement was an income tax expense of $25 million and $1 million for discontinued operations for the three- and nine-months ended September 30, 2013, respectively. Operating revenue and loss before income taxes for discontinued operations were $461 million and $262 million, respectively, for the three months ended September 30, 2012, and $1.31 billion and $645 million, respectively, for the nine months ended September 30, 2012.
	Contingencies
	Edison International Parent has not guaranteed the obligations of EME, however, under the Internal Revenue Code and applicable state statutes, Edison International Parent is jointly liable for qualified retirement plans and federal and specific state tax liabilities. As a result of the deconsolidation and the existence of joint liabilities, Edison International has recorded liabilities of $80 million for qualified retirement plans related to plan participants of EME and $192 million of liabilities related to joint tax liabilities. Under the qualified plan documents and tax allocation agreements, EME is obligated to pay for such liabilities and, accordingly, Edison International has recorded receivables of $238 million from EME net of amounts recorded in accumulated other comprehensive income of $34 million (related to actuarial losses under the qualified retirement plans).
	If the Settlement Transaction had been approved and implemented, Edison International Parent would not have been entitled to receive reimbursement of the net receivable of $46 million and would be obligated to assume certain other retirement liabilities as specified in such agreement (estimated at $104 million). Inasmuch as the Settlement Transaction has been terminated, Edison International Parent will seek recovery of such joint liabilities as part of the EME bankruptcy proceeding. The outcome of the EME bankruptcy proceeding is uncertain, as was the disposition of the Support Agreement. Accordingly, management judgment was required to assess the collectibility of the receivables recorded and outcome of the bankruptcy proceeding. Management concluded that it is probable that a loss would be incurred and estimated a loss of $150 million. The outcome of the EME bankruptcy could result in losses different than the amounts recorded by Edison International and such amounts could be material.
	For a discussion of other contingencies related to EME, see Tax Disputes discussed in Note 7 and potential litigation discussed in Note 12.

Supplemental_Cash_Flows_Inform

Supplemental Cash Flows Information	9 Months Ended
	Sep. 30, 2013
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flows Information	Supplemental Cash Flows Information
	Supplemental cash flows information for continuing operations is:
		Edison International					SCE
		Nine months ended September 30,
	(in millions)	2013		2012			2013		2012
	Cash payments (receipts) for interest and taxes:
	Interest, net of amounts capitalized	$	431	$	394		$	415	$	394
	Tax payments (refunds), net	27		(239		)	18		(243		)
	Non-cash financing and investing activities:
	Dividends declared but not paid:
	Common stock	$	110	$	106		$	120	$	—
	Preferred and preference stock	4		6			4		6
	SCE's accrued capital expenditures at September 30, 2013 and 2012 were $401 million and $414 million, respectively. Accrued capital expenditures will be included as an investing activity in the consolidated statements of cash flow in the period paid.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2013
Accounting Policies [Abstract]
Organization and Basis of Presentation	Organization and Basis of Presentation
	Edison International is the parent holding company of Southern California Edison Company ("SCE"). SCE is an investor-owned public utility primarily engaged in the business of supplying electricity to an approximately 50,000 square mile area of southern California. Edison International is also the parent company of nonutility subsidiaries that are engaged in competitive businesses related to the delivery or use of electricity. Such competitive business activities are currently not material to report as a separate business segment. These combined notes to the consolidated financial statements apply to both Edison International and SCE unless otherwise described. Edison International's consolidated financial statements include the accounts of Edison International, SCE and other wholly owned and controlled subsidiaries. References to Edison International refer to the consolidated group of Edison International and its subsidiaries. References to Edison International Parent and Other refer to Edison International Parent and its nonutility subsidiaries. SCE's consolidated financial statements include the accounts of SCE and its wholly owned and controlled subsidiaries. All intercompany transactions have been eliminated from the consolidated financial statements.
	Edison International's and SCE's significant accounting policies were described in Note 1 of "Notes to Consolidated Financial Statements" included in the 2012 Form 10-K. The same accounting policies are followed for interim reporting purposes, with the exception of accounting principles adopted as of January 1, 2013, discussed below in "—New Accounting Guidance." This quarterly report should be read in conjunction with the financial statements and notes included in the 2012 Form 10-K.
	Beginning in the fourth quarter of 2012, Edison Mission Energy ("EME") met the definition of a discontinued operation and was classified separately in Edison International's consolidated financial statements. Except as indicated, amounts in the notes to the consolidated financial statements relate to continuing operations of Edison International. See Note 16 for information related to discontinued operations.
	In the opinion of management, all adjustments, consisting of recurring accruals, have been made that are necessary to fairly state the consolidated financial position, results of operations and cash flows in accordance with accounting principles generally accepted in the United States of America for the periods covered by this quarterly report on Form 10-Q. The results of operations for the three- and nine-month periods ended September 30, 2013 are not necessarily indicative of the operating results for the full year.
	The December 31, 2012 condensed consolidated balance sheet data was derived from audited financial statements, but does not include all disclosures required by accounting principles generally accepted in the United States of America.
Cash Equivalents	Cash Equivalents
	Cash equivalents included investments in money market funds. Generally, the carrying value of cash equivalents equals the fair value, as these investments have original maturities of three months or less.
	Cash is temporarily invested until required for check clearing from the primary disbursement accounts.
Inventory	Inventory
	Inventory is stated at the lower of cost or market, cost being determined by the weighted-average cost method for fuel, and the average cost method for materials, supplies and spare parts.
Greenhouse Gas Emission Allowances	Greenhouse Gas Allowances
	SCE is allocated greenhouse gas ("GHG") allowances annually which it is then required to sell them into quarterly auctions. GHG proceeds from the auction are recorded as a regulatory liability to be refunded to customers. SCE purchases GHG allowances from quarterly auctions or bilateral parties to satisfy its compliance obligations and recovers such costs of GHG from customers. GHG allowances held for use are classified as "Other current assets" on the consolidated balance sheets and are stated at the lower of weighted-average cost or market.
Earnings Per Share	Earnings Per Share
	Edison International computes earnings per share ("EPS") using the two-class method, which is an earnings allocation formula that determines EPS for each class of common stock and participating security. Edison International's participating securities are stock-based compensation awards payable in common shares, including stock options, performance shares and restricted stock units, which earn dividend equivalents on an equal basis with common shares. Stock options awarded during the period 2003 through 2006 received dividend equivalents.
New Accounting Guidance	New Accounting Guidance
	Accounting Guidance Adopted in 2013
	Offsetting Assets and Liabilities
	In January 2013, the FASB issued accounting standard updates modifying the disclosure requirements about the nature of an entity's rights of offsetting recognized assets and liabilities in the statement of financial position under master netting agreements and similar arrangements associated with derivative instruments, repurchase agreements and securities lending transactions. The guidance requires increased disclosure of the gross and net recognized assets and liabilities, collateral positions and descriptions of setoff rights. Edison International and SCE adopted this guidance effective January 1, 2013. The adoption of this standard did not impact the consolidated income statements, balance sheets or cash flows of Edison International or SCE. See Note 6 for further details.
	Items Reclassified out of Accumulated Other Comprehensive Income
	In February 2013, the FASB issued an accounting standards update which requires disclosure related to items reclassified out of accumulated other comprehensive income ("AOCI"). The guidance requires companies to present separately, for each component of other comprehensive income, current period reclassifications and the remainder of the current-period other comprehensive income. In addition, for certain current period reclassifications, an entity is required to disclose the effect of the item reclassified out of AOCI on the respective line item(s) of net income. Edison International and SCE adopted this guidance effective January 1, 2013. See Note 14 for further details.
	Accounting Guidance Not Yet Adopted
	In July 2013, the FASB issued an accounting standards update that will require that an unrecognized tax benefit be presented on the balance sheet as a reduction of a deferred tax asset for a net operating loss ("NOL") or tax credit carryforward under certain circumstances. This proposal is effective January 1, 2014 and is not expected to have a material impact on the consolidated financial statements.

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2013
Accounting Policies [Abstract]
Cash Equivalents	Checks issued, but not yet paid by the financial institution, are reclassified from cash to accounts payable at the end of each reporting period as follows:
		Edison International					SCE
	(in millions)	September 30,		December 31, 2012			September 30,		December 31, 2012
		2013					2013
	Uncleared checks reclassified to accounts payable	$	202	$	247		$	201	$	242
	The cash equivalents were as follows:
		Edison International					SCE
	(in millions)	September 30,		December 31, 2012			September 30,		December 31, 2012
		2013					2013
	Money market funds	$	518	$	107		$	453	$	5
Inventory Components	Inventory consisted of the following:
	(in millions)	September 30,		December 31, 2012
		2013
	Materials, supplies and spare parts	$	250	$	319
	Fuel	22		21
	Total inventory	$	272	$	340
EPS Attributable to Edison International Common Shareholders	EPS attributable to Edison International common shareholders was computed as follows:
		Three months ended September 30,					Nine months ended
							September 30,
	(in millions)	2013		2012			2013		2012
	Basic earnings per share – continuing operations:
	Income from continuing operations available to common shareholders	$	463	$	357		$	615	$	717
	Weighted average common shares outstanding	326		326			326		326
	Basic earnings per share – continuing operations	$	1.42	$	1.09		$	1.88	$	2.2
	Diluted earnings per share – continuing operations:
	Income from continuing operations available to common shareholders	$	463	$	357		$	615	$	717
	Income impact of assumed conversions	—		—			1		—
	Income from continuing operations available to common shareholders and assumed conversions	$	463	$	357		$	616	$	717
	Weighted average common shares outstanding	326		326			326		326
	Incremental shares from assumed conversions	2		3			3		2
	Adjusted weighted average shares – diluted	328		329			329		328
	Diluted earnings per share – continuing operations	$	1.41	$	1.09		$	1.87	$	2.18
Asset Retirement Obligation
	(in millions)	September 30,		December 31,
		2013		2012
	Beginning balance	$	2,782	$	2,610
	Accretion expense1	134		161
	Revisions	455		12
	Liabilities settled	—		(1		)
	Ending balance	$	3,371	$	2,782

Consolidated_Statements_of_Cha1

Consolidated Statements of Changes in Equity (Tables)	9 Months Ended
	Sep. 30, 2013
Statement of Stockholders' Equity [Abstract]
Schedule of changes in equity	The following table provides Edison International's changes in equity for the nine months ended September 30, 2013:
		Equity Attributable to Edison International																Noncontrolling Interests
	(in millions)	Common				Accumulated				Retained				Subtotal				Preferred				Total
		Stock				Other				Earnings								and				Equity
						Comprehensive												Preference
						Loss												Stock
	Balance at December 31, 2012	$	2,373			$	(87	)		$	7,146			$	9,432			$	1,759			$	11,191
	Net income	—				—				614				614				75				689
	Other comprehensive income	—				8				—				8				—				8
	Common stock dividends declared ($1.0125 per share)	—				—				(330		)		(330		)		—				(330		)
	Dividends, distributions to noncontrolling interests	—				—				—				—				(75		)		(75		)
	Stock-based compensation and other	5				—				(45		)		(40		)		—				(40		)
	Noncash stock-based compensation and other	19				—				(6		)		13				(1		)		12
	Issuance of preference stock	—				—				—				—				387				387
	Redemption of preference stock	—				—				(8		)		(8		)		(392		)		(400		)
	Balance at September 30, 2013	$	2,397			$	(79	)		$	7,371			$	9,689			$	1,753			$	11,442
	During the first quarter of 2013, SCE redeemed all outstanding shares of Series B and C preference stock and charged the issuance costs to retained earnings.
	The following table provides Edison International's changes in equity for the nine months ended September 30, 2012:
		Equity Attributable to Edison International															Noncontrolling Interests
	(in millions)	Common			Accumulated				Retained				Subtotal				Other				Preferred				Total
		Stock			Other				Earnings												and				Equity
					Comprehensive																Preference
					Loss																Stock
	Balance at December 31, 2011	$	2,360		$	(139	)		$	7,834			$	10,055			$	2			$	1,029			$	11,086
	Net income	—			—				357				357				—				66				423
	Other comprehensive loss	—			(29		)		—				(29		)		—				—				(29		)
	Contributions from noncontrolling interests	—			—				—				—				238				—				238
	Transfer of assets to Capistrano Wind Partners	(21		)	—				—				(21		)		—				—				(21		)
	Common stock dividends declared ($0.975 per share)	—			—				(318		)		(318		)		—				—				(318		)
	Dividends, distributions to noncontrolling interests and other	—			—				—				—				(2		)		(66		)		(68		)
	Stock-based compensation and other	19			—				(64		)		(45		)		—				—				(45		)
	Noncash stock-based compensation and other	27			—				(2		)		25				—				—				25
	Issuance of preference stock	—			—				—				—				—				804				804
	Redemption of preference stock	—			—				(1		)		(1		)		—				(74		)		(75		)
	Balance at September 30, 2012	$	2,385		$	(168	)		$	7,806			$	10,023			$	238			$	1,759			$	12,020
	The following table provides SCE's changes in equity for the nine months ended September 30, 2013:
		Equity Attributable to SCE
	(in millions)	Common				Additional				Accumulated				Retained				Preferred				Total
		Stock				Paid-in				Other				Earnings				and				Equity
						Capital				Comprehensive								Preference
										Loss								Stock
	Balance at December 31, 2012	$	2,168			$	581			$	(29	)		$	7,228			$	1,795			$	11,743
	Net income	—				—				—				717				—				717
	Other comprehensive income	—				—				1				—				—				1
	Dividends declared on common stock	—				—				—				(360		)		—				(360		)
	Dividends declared on preferred and preference stock	—				—				—				(75		)		—				(75		)
	Stock-based compensation and other	—				3				—				(39		)		—				(36		)
	Noncash stock-based compensation and other	—				10				—				4				—				14
	Issuance of preference stock	—				(13		)		—				—				400				387
	Redemption of preference stock	—				8				—				(8		)		(400		)		(400		)
	Balance at September 30, 2013	$	2,168			$	589			$	(28	)		$	7,467			$	1,795			$	11,991
	During the first quarter of 2013, SCE redeemed all outstanding shares of Series B and C preference stock and charged the issuance costs to retained earnings.
	The following table provides SCE's changes in equity for the nine months ended September 30, 2012:
		Equity Attributable to SCE
	(in millions)	Common				Additional				Accumulated				Retained				Preferred				Total
		Stock				Paid-in				Other				Earnings				and				Equity
						Capital				Comprehensive								Preference
										Loss								Stock
	Balance at December 31, 2011	$	2,168			$	596			$	(24	)		$	6,173			$	1,045			$	9,958
	Net income	—				—				—				802				—				802
	Other comprehensive income	—				—				1				—				—				1
	Dividends declared on common stock	—				—				—				(349		)		—				(349		)
	Dividends declared on preferred and preference stock	—				—				—				(66		)		—				(66		)
	Stock-based compensation and other	—				11				—				(35		)		—				(24		)
Noncash stock-based compensation and other	—				13				—				—				—				13
Issuance of preference stock	—				(21		)		—				—				825				804
Redemption of preference stock	—				1				—				(1		)		(75		)		(75		)
Balance at September 30, 2012	$	2,168			$	600			$	(23	)		$	6,524			$	1,795			$	11,064

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2013
Fair Value Disclosures [Abstract]
Fair Value by Level	The following table sets forth assets and liabilities of SCE that were accounted for at fair value by level within the fair value hierarchy:
		September 30, 2013
	(in millions)	Level 1				Level 2				Level 3				Netting				Total
														and
														Collateral1
	Assets at fair value
	Money market funds	$	453			$	—			$	—			$	—			$	453
	Mutual funds	29				—				—				—				29
	Derivative contracts:
	Congestion revenue rights	—				—				245				—				245
	Electricity	—				1				—				—				1
	Natural gas	—				1				—				(1		)		—
	Tolling	—				—				8				—				8
	Subtotal of derivative contracts	—				2				253				(1		)		254
	Long-term disability plan	8				—				—				—				8
	Nuclear decommissioning trusts:
	Stocks2	2,027				—				—				—				2,027
	U.S. government and agency securities	823				101				—				—				924
	Municipal bonds	—				796				—				—				796
	Corporate bonds	—				221				—				—				221
	Short-term investments, primarily cash equivalents4	322				45				—				—				367
	Subtotal of nuclear decommissioning trusts	3,172				1,163				—				—				4,335
	Total assets	3,662				1,165				253				(1		)		5,079
	Liabilities at fair value
	Derivative contracts:
	Electricity	—				5				12				(3		)		14
	Natural gas	—				43				—				(18		)		25
	Tolling	—				—				1,272				—				1,272
	Subtotal of derivative contracts	—				48				1,284				(21		)		1,311
	Total liabilities	—				48				1,284				(21		)		1,311
	Net assets (liabilities)	$	3,662			$	1,117			$	(1,031	)		$	20			$	3,768
		December 31, 2012
	(in millions)	Level 1				Level 2				Level 3				Netting				Total
														and
														Collateral1
	Assets at fair value
	Money market funds	$	5			$	—			$	—			$	—			$	5
	Derivative contracts:
	Congestion revenue rights	—				—				186				—				186
	Electricity	—				—				31				(13		)		18
	Natural gas	—				8				—				(2		)		6
	Tolling	—				—				4				—				4
	Subtotal of derivative contracts	—				8				221				(15		)		214
	Long-term disability plan	8				—				—				—				8
	Nuclear decommissioning trusts:
	Stocks2	2,271				—				—				—				2,271
	Municipal bonds	—				644				—				—				644
	U.S. government and agency securities	477				126				—				—				603
	Corporate bonds	—				410				—				—				410
	Short-term investments, primarily cash equivalents4	121				—				—				—				121
	Subtotal of nuclear decommissioning trusts	2,869				1,180				—				—				4,049
	Total assets	2,882				1,188				221				(15		)		4,276
	Liabilities at fair value
	Derivative contracts:
	Electricity	—				2				5				(2		)		5
	Natural gas	—				113				2				(60		)		55
	Tolling	—				—				1,005				—				1,005
	Subtotal of derivative contracts	—				115				1,012				(62		)		1,065
	Total liabilities	—				115				1,012				(62		)		1,065
	Net assets (liabilities)	$	2,882			$	1,073			$	(791	)		$	47			$	3,211
	1	Represents the netting of assets and liabilities under master netting agreements and cash collateral across the levels of the fair value hierarchy. Netting among positions classified within the same level is included in that level.
	2	Approximately 69% and 66% of SCE's equity investments were located in the United States at September 30, 2013 and December 31, 2012, respectively.
	3	At September 30, 2013 and December 31, 2012, SCE's corporate bonds were diversified and included collateralized mortgage obligations and other asset backed securities of $32 million and $56 million, respectively.
	4	Excludes net payables of $3 million and $1 million at September 30, 2013 and December 31, 2012, respectively, of interest and dividend receivables as well as receivables and payables related to SCE's pending securities sales and purchases.
Summary of Changes in Fair Value of Level 3 Net Derivative Assets and Liabilities	The following table sets forth a summary of changes in SCE's fair value of Level 3 net derivative assets and liabilities:
			Three months ended September 30,								Nine months ended
											September 30,
	(in millions)		2013				2012				2013				2012
	Fair value of net liabilities at beginning of period		$	(967	)		$	(739	)		$	(791	)		$	(754	)
	Total realized/unrealized gains (losses):
	Included in regulatory assets and liabilities1		(50		)		(180		)		(205		)		(203		)
	Purchases		19				33				56				84
	Settlements		(33		)		(44		)		(91		)		(57		)
	Fair value of net liabilities at end of period		$	(1,031	)		$	(930	)		$	(1,031	)		$	(930	)
	Change during the period in unrealized losses related to assets and liabilities held at the end of the period		$	(65	)		$	(222	)		$	(198	)		$	(244	)
	1	Due to regulatory mechanisms, SCE's realized and unrealized gains and losses are recorded as regulatory assets and liabilities.
Valuation Techniques and Significant Unobservable Inputs Used to Determine Fair Value for Level 3 Assets and Liabilities	The following table sets forth SCE's valuation techniques and significant unobservable inputs used to determine fair value for Level 3 assets and liabilities:
		Fair Value (in millions)								Significant	Range
	September 30, 2013	Assets				Liabilities			Valuation Technique(s)	Unobservable Input	(Weighted Average)
	Electricity:
	Options	$	2			$	10		Option model	Volatility of gas prices	24% - 30% (28%)
										Volatility of power prices	28% - 45% (39%)
										Power prices	$40.60 - $49.80 ($43.50)
	Forwards	—				4			Discounted cash flow	Power prices	$7.70 - $40.80 ($31.40)
	CRRs	245				—			Market simulation model	Load forecast	7,603 MW - 24,896 MW
										Power prices	$(9.86) - $108.56
										Gas prices	$3.50 - $7.10
	Tolling	8				1,272			Option model	Volatility of gas prices	16% - 30% (19%)
										Volatility of power prices	25% - 45% (29%)
										Power prices	$35.90 - $62.60 ($46.90)
	Netting	(2		)		(2		)
	Total derivative contracts	$	253			$	1,284
		Fair Value (in millions)								Significant	Range
	31-Dec-12	Assets				Liabilities			Valuation Technique(s)	Unobservable Input	(Weighted Average)
	Electricity:
	Options	$	40			$	12		Option model	Volatility of gas prices	25% - 36% (33%)
										Volatility of power prices	29% - 64% (42%)
										Power prices	$41.70 - $59.20 ($47.00)
	Forwards	2				4			Discounted cash flow	Power prices	$23.10 - $44.90 ($31.10)
	CRRs	186				—			Market simulation model	Load forecast	7,597 MW - 26,612 MW
										Power prices	$(13.90) - $226.75
										Gas prices	$2.95 - $7.78
	Gas options	—				2			Option model	Volatility of gas prices	28% - 36% (34%)
	Tolling	4				1,005			Option model	Volatility of gas prices	17% - 36% (22%)
										Volatility of power prices	26% - 64% (29%)
										Power prices	$35.00 - $84.10 ($55.40)
	Netting	(11		)		(11		)
	Total derivative contracts	$	221			$	1,012
Carrying Amounts and Fair Values of Long-term Debt, Including Current Portion	The carrying value and fair value of Edison International and SCE's long-term debt is as follows:
		September 30, 2013								December 31, 2012
	(in millions)	Carrying				Fair				Carrying				Fair
		Value				Value				Value				Value
	SCE	$	8,828			$	9,590			$	8,828			$	10,505
	Edison International	9,232				10,016				9,231				10,944

Derivative_Instruments_Tables

Derivative Instruments (Tables)	9 Months Ended
	Sep. 30, 2013
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair Value of Derivative Instruments	The following table summarizes the gross and net fair values of SCE's commodity derivative instruments:
			September 30, 2013
			Derivative Assets										Derivative Liabilities
	(in millions)		Short-Term				Long-Term			Subtotal			Short-Term			Long-Term			Subtotal			Net
																						Liability
	Commodity derivative contracts
	Gross amounts recognized		$	53			$	207		$	260		$	195		$	1,143		$	1,338		$	1,078
	Gross amounts offset in the consolidated balance sheets		(6		)		—			(6		)	(6		)	—			(6		)	—
	Cash collateral posted1		—				—			—			(15		)	(6		)	(21		)	(21		)
	Net amounts presented in the consolidated balance sheets		$	47			$	207		$	254		$	174		$	1,137		$	1,311		$	1,057
			December 31, 2012
			Derivative Assets										Derivative Liabilities
	(in millions)		Short-Term				Long-Term			Subtotal			Short-Term			Long-Term			Subtotal			Net
																						Liability
	Commodity derivative contracts
	Gross amounts recognized		$	151			$	91		$	242		$	186		$	954		$	1,140		$	898
	Gross amounts offset in the consolidated balance sheets		(22		)		(6		)	(28		)	(22		)	(6		)	(28		)	—
	Cash collateral posted1		—				—			—			(38		)	(9		)	(47		)	(47		)
	Net amounts presented in the consolidated balance sheets		$	129			$	85		$	214		$	126		$	939		$	1,065		$	851
	1	In addition, at September 30, 2013 and December 31, 2012, SCE had posted $14 million and $8 million, respectively, of collateral that is not offset against the derivative liabilities and is reflected in "Other current assets" on the consolidated balance sheets.
Summarization of Economic Hedging Activities	The following table summarizes the components of SCE's economic hedging activity:
			Three months ended September 30,							Nine months ended
										September 30,
	(in millions)		2013				2012			2013			2012
	Realized losses		$	(15	)		$	(77	)	$	(38	)	$	(199	)
	Unrealized losses		(41		)		(91		)	(159		)	(29		)
Notional Volumes of Derivative Instruments	The following table summarizes the notional volumes of derivatives used for SCE hedging activities:
			Economic Hedges
	Commodity	Unit of Measure	September 30,			December 31, 2012
			2013
	Electricity options, swaps and forwards	GWh	8,964			15,884
	Natural gas options, swaps and forwards	Bcf	12			100
	Congestion revenue rights	GWh	127,772			149,774
	Tolling arrangements	GWh	97,893			101,485

Income_Taxes_Tables

Income Taxes (Tables)	9 Months Ended
	Sep. 30, 2013
Income Tax Disclosure [Abstract]
Reconciliation of income tax expense	The table below provides a reconciliation of income tax expense computed at the federal statutory income tax rate to the income tax provision:
		Three months ended September 30,						Nine months ended
								September 30,
	(in millions)	2013			2012			2013			2012
	Edison International:
	Income from continuing operations before income taxes	$	665		$	610		$	863		$	1,204
	Provision for income tax at federal statutory rate of 35%	233			214			302			421
	Increase (decrease) in income tax from:
	State tax, net of federal benefit	22			46			5			60
	Property-related	(57		)	(20		)	(121		)	(39		)
	Uncertain tax positions	(5		)	1			13			2
	Other	(16		)	(13		)	(26		)	(23		)
	Total income tax expense from continuing operations	$	177		$	228		$	173		$	421
	Effective tax rate	26.6		%	37.4		%	20		%	35		%
	SCE:
	Income from continuing operations before income taxes	$	685		$	564		$	913		$	1,186
	Provision for income tax at federal statutory rate of 35%	240			197			319			415
	Increase (decrease) in income tax from:
	State tax, net of federal benefit	21			10			12			30
	Property-related	(57		)	(19		)	(121		)	(39		)
	Uncertain tax positions	(6		)	1			11			1
	Other	(15		)	(13		)	(25		)	(23		)
	Total income tax expense from continuing operations	$	183		$	176		$	196		$	384
	Effective tax rate	26.7		%	31.2		%	21.5		%	32.4		%

Compensation_and_Benefit_Plans1

Compensation and Benefit Plans (Tables)	9 Months Ended
	Sep. 30, 2013
Workforce Reductions [Abstract]
Workforce reductions	The following table provides a summary of changes in the accrued severance liability associated with these reductions:
	(in millions)
	Balance at January 1, 2013		$	104
	Additions		109
	Payments		(132		)
	Balance at September 30, 2013		$	81
Pension Plans
Pension and Other Postretirement Benefits
Expense Components for Plans	Expense components for continuing operations are:
		Three months ended September 30,							Nine months ended
									September 30,
	(in millions)	2013				2012			2013			2012
	Edison International:
	Service cost	$	38			$	44		$	114		$	121
	Interest cost	42				46			126			137
	Expected return on plan assets	(58		)		(53		)	(172		)	(164		)
	Settlement costs1	24				1			73			4
	Amortization of prior service cost	1				1			3			3
	Amortization of net loss2	15				18			45			48
	Expense under accounting standards	$	62			$	57		$	189		$	149
	Regulatory adjustment (deferred)	(7		)		(57		)	(21		)	(3		)
	Total expense recognized	$	55			$	—		$	168		$	146
	SCE:
	Service cost	$	37			$	46		$	111		$	120
	Interest cost	41				45			123			135
	Expected return on plan assets	(57		)		(52		)	(171		)	(162		)
	Settlement costs	24				1			72			3
	Amortization of prior service cost	1				1			3			3
	Amortization of net loss2	14				14			42			42
	Expense under accounting standards	$	60			$	55		$	180		$	141
	Regulatory adjustment (deferred)	(7		)		(57		)	(21		)	(3		)
	Total expense recognized	$	53			$	(2	)	$	159		$	138
	1	Includes the amount of net loss reclassified from other comprehensive loss. The amount reclassified for Edison International was $2 million for the nine months ended September 30, 2013.
	2	Includes the amount of net loss reclassified from other comprehensive loss. The amount reclassified for Edison International and SCE was $4 million and $3 million for the three months ended September 30, 2013, respectively, and $11 million and $8 million for the nine months ended September 30, 2013, respectively.
Postretirement Benefits Other Than Pensions
Pension and Other Postretirement Benefits
Expense Components for Plans	Expense components for continuing operations are:
		Three months ended September 30,							Nine months ended
									September 30,
	(in millions)	2013				2012			2013			2012
	Edison International:
	Service cost	$	14			$	13		$	42		$	37
	Interest cost	26				28			78			85
	Expected return on plan assets	(30		)		(27		)	(90		)	(81		)
	Special termination benefits1	—				3			10			3
	Amortization of prior service credit	(9		)		(9		)	(27		)	(27		)
	Amortization of net loss2	7				12			21			35
	Total expense	$	8			$	20		$	34		$	52
	SCE:
	Service cost	$	14			$	12		$	41		$	36
	Interest cost	26				28			78			84
	Expected return on plan assets	(30		)		(27		)	(90		)	(81		)
	Special termination benefits1	—				3			10			3
	Amortization of prior service credit	(9		)		(9		)	(27		)	(27		)
	Amortization of net loss2	7				11			21			33
	Total expense	$	8			$	18		$	33		$	48
	1	Due to the reduction in workforce, SCE has incurred costs for extended retiree health care coverage.
	2	Includes the amount of net loss reclassified from other comprehensive loss. The amount reclassified for Edison International and SCE was less than $1 million and zero for the three- and nine-months ended September 30, 2013, respectively.

Other_Investments_Tables

Other Investments (Tables)	9 Months Ended
	Sep. 30, 2013
Regulated Entity, Other Assets, Noncurrent [Abstract]
Amortized Cost and Fair Value of the Trust Investments	The following table sets forth amortized cost and fair value of the trust investments:
		Longest		Amortized Cost								Fair Value
		Maturity
	(in millions)	Dates		September 30,				December 31,				September 30,				December 31, 2012
				2013				2012				2013
	Stocks	—		$	635			$	978			$	2,027			$	2,271
	Municipal bonds	2051		701				518				796				644
	U.S. government and agency securities	2043		861				547				924				603
	Corporate bonds	2054		176				324				221				410
	Short-term investments, primarily cash equivalents	One-year		351				117				367				121
	Total investments			2,724				2,484				4,335				4,049
	Net payables			(3		)		(1		)		(3		)		(1		)
	Total nuclear decommissioning trusts			$	2,721			$	2,483			$	4,332			$	4,048
Summary of Changes in the Fair Value of Trust	The following table sets forth a summary of changes in the fair value of the trust:
		Three months ended September 30,								Nine months ended
										September 30,
	(in millions)	2013				2012				2013				2012
	Balance at beginning of period	$	4,182			$	3,810			$	4,048			$	3,592
	Gross realized gains	119				13				261				54
	Gross realized losses	(17		)		—				(18		)		(5		)
	Unrealized gains, net	55				156				46				272
	Other-than-temporary impairments	(15		)		(7		)		(44		)		(30		)
	Interest, dividends, contributions and other	8				25				39				114
	Balance at end of period	$	4,332			$	3,997			$	4,332			$	3,997

Regulatory_Assets_and_Liabilit1

Regulatory Assets and Liabilities (Tables)	9 Months Ended
	Sep. 30, 2013
Regulatory Assets and Liabilities Disclosure [Abstract]
Regulatory Assets Included on the Consolidated Balance Sheets	Regulatory assets included on the consolidated balance sheets are:
	(in millions)	September 30,		December 31,
		2013		2012
	Current:
	Regulatory balancing accounts	$	344	$	502
	Energy derivatives	162		70
	Total current	506		572
	Long-term:
	Deferred income taxes, net	2,911		2,663
	Pensions and other postretirement benefits	1,105		1,550
	Energy derivatives	960		900
	Unamortized investments, net	358		507
	San Onofre	1,450		—
	Unamortized loss on reacquired debt	213		228
	Nuclear-related investment, net	34		141
	Regulatory balancing accounts	626		73
	Other	358		360
	Total long-term	8,015		6,422
	Total regulatory assets	$	8,521	$	6,994
Regulatory Liabilities Included on the Consolidated Balance Sheets	Regulatory liabilities included on the consolidated balance sheets are:
	(in millions)	September 30,		December 31,
		2013		2012
	Current:
	Regulatory balancing accounts	$	580	$	484
	Other	49		52
	Total current	629		536
	Long-term:
	Costs of removal	2,814		2,731
	Asset retirement obligations	954		1,385
	Regulatory balancing accounts	1,210		1,091
	Other	11		7
	Total long-term	4,989		5,214
	Total regulatory liabilities	$	5,618	$	5,750

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Loss (Tables)	9 Months Ended
	Sep. 30, 2013
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Components of Accumulated Other Comprehensive Loss	Accumulated other comprehensive loss, net of tax, consists of:
		Pension and PBOP – Net Loss
	(in millions)	Three months ended September 30, 2013			Nine months ended September 30, 2013
	Edison International:
	Balance at beginning of period	$	(82	)	$	(87	)
	Other comprehensive loss before reclassifications	—			(2		)
	Amounts reclassified from accumulated other comprehensive loss1	3			10
	Net current-period other comprehensive loss	3			8
	Balance at end of period	$	(79	)	$	(79	)
	Reclassifications from accumulated other comprehensive loss:
	Amortization of net loss included in net income	$	4		$	13
	Tax expense	1			3
	Total reclassification, net of tax	$	3		$	10
	SCE:
	Balance at beginning of period	$	(30	)	$	(29	)
	Other comprehensive loss before reclassifications	—			(4		)
	Amounts reclassified from accumulated other comprehensive loss1	2			5
	Net current-period other comprehensive loss	2			1
	Balance at end of period	$	(28	)	$	(28	)
	Reclassifications from accumulated other comprehensive loss:
	Amortization of net loss included in net income	$	3		$	8
	Tax expense	1			3
	Total reclassification, net of tax	$	2		$	5
	1	These items are included in the computation of net periodic pension and PBOP expense. See Note 8 for additional information.

Interest_and_Other_Income_and_1

Interest and Other Income and Expenses (Tables)	9 Months Ended
	Sep. 30, 2013
Other Income and Expenses [Abstract]
Interest and Other Income and Expenses	Interest and other income and expenses are as follows:
		Three months ended September 30,				Nine months ended
						September 30,
	(in millions)	2013		2012		2013		2012
	SCE interest and other income:
	Equity allowance for funds used during construction	$	14	$	23	$	54	$	71
	Increase in cash surrender value of life insurance policies	10		6		24		20
	Interest income	2		2		8		5
	Other	1		7		3		12
	Total SCE interest and other income	27		38		89		108
	Edison International Parent and Other income	1		—		2		2
	Total Edison International interest and other income	$	28	$	38	$	91	$	110
	SCE other expenses:
	Civic, political and related activities and donations	$	9	$	5	$	24	$	22
	Other	6		4		14		14
	Total SCE other expenses	15		9		38		36
	Edison International Parent and Other other expenses	—		1		—		—
	Total Edison International other expenses	$	15	$	10	$	38	$	36

Supplemental_Cash_Flows_Inform1

Supplemental Cash Flows Information (Tables)	9 Months Ended
	Sep. 30, 2013
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flows Information	Supplemental cash flows information for continuing operations is:
		Edison International					SCE
		Nine months ended September 30,
	(in millions)	2013		2012			2013		2012
	Cash payments (receipts) for interest and taxes:
	Interest, net of amounts capitalized	$	431	$	394		$	415	$	394
	Tax payments (refunds), net	27		(239		)	18		(243		)
	Non-cash financing and investing activities:
	Dividends declared but not paid:
	Common stock	$	110	$	106		$	120	$	—
	Preferred and preference stock	4		6			4		6

Summary_of_Significant_Account3

Summary of Significant Accounting Policies (Details) (Southern California Edison, Electric Utility)	9 Months Ended
	Sep. 30, 2013
	sqmi
Southern California Edison | Electric Utility
Summary of Significant Accounting Policies [Line Items]
Supply of electricity, area covered (square mile)	50,000

Summary_of_Significant_Account4

Summary of Significant Accounting Policies (Cash) (Details) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Cash and Cash Equivalents Items [Line Items]
Maximum maturity period of cash equivalent investments (in months)	3 months
Money market funds	$518	$107
Cash reclassified to accounts payable	202	247
Southern California Edison
Cash and Cash Equivalents Items [Line Items]
Money market funds	453	5
Cash reclassified to accounts payable	$201	$242

Summary_of_Significant_Account5

Summary of Significant Accounting Policies (Inventory) (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2012	31-May-13	31-May-13
In Millions, unless otherwise specified			Southern California Edison	Southern California Edison	San Onofre (nuclear)	San Onofre (nuclear)
					Southern California Edison	Inventory
						Southern California Edison
Summary of Significant Accounting Policies [Line Items]
Materials and supplies, and spare parts			$250	$319
Fuel			22	21
Total inventory	272	340	272	340
Amount of assets reclassified to a regulatory asset					$1,521	$100

Summary_of_Significant_Account6

Summary of Significant Accounting Policies (Earnings Per Share) (Details) (USD $)	3 Months Ended			9 Months Ended
In Millions, except Share data, unless otherwise specified	Sep. 30, 2013		Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Basic earnings per share - continuing operations:
Income from continuing operations available to common shareholders	$463		$357	$615	$717
Weighted average common shares outstanding (in shares)	326,000,000		326,000,000	326,000,000	326,000,000
Basic earnings per share b continuing operations (in dollars per share)	$1.42		$1.09	$1.88	$2.20
Diluted earnings per share - continuing operations:
Income from continuing operations available to common shareholders	463		357	615	717
Income impact of assumed conversions	0		0	1	0
Income from continuing operations available to common shareholders and assumed conversions	$463		$357	$616	$717
Weighted average common shares outstanding (in shares)	326,000,000		326,000,000	326,000,000	326,000,000
Incremental shares from assumed conversions (in shares)	2,000,000	[1]	3,000,000	3,000,000	2,000,000
Adjusted weighted average shares - diluted (in shares)	328,000,000		329,000,000	329,000,000	328,000,000
Diluted earnings per share b continuing operations (in dollars per share)	$1.41		$1.09	$1.87	$2.18
Stock-Based Compensation Awards
Diluted earnings per share - continuing operations:
Stock-based compensation awards excluded from the computation of diluted earnings per share (in shares)	4,109,363		3,238,581	4,109,363	4,819,683
[1]

Summary_of_Significant_Account7

Summary of Significant Accounting Policies (Asset Retirement Obligation) (Details) (USD $)	9 Months Ended	12 Months Ended	3 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012	Jun. 30, 2013	Sep. 30, 2013
			San Onofre (nuclear)	San Onofre (nuclear)
Significant Accounting Policies [Line Items]
Increase in ARO liability			$455
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	2,782	2,610		2,710
Accretion expense	134	161
Revisions	455	12
Liabilities settled	0	-1
Ending balance	$3,371	$2,782		$2,710

Summary_of_Significant_Account8

Summary of Significant Accounting Policies (Related Party) (Details) (Southern California Edison, Edison Mission Energy, USD $)	3 Months Ended	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2013
		MW
Southern California Edison | Edison Mission Energy
Significant Accounting Policies [Line Items]
Length of contract		10 years
Plant output		479
Expense for power purchased	$64	$70

Consolidated_Statements_of_Cha2

Consolidated Statements of Changes in Equity (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, except Per Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period			$11,191	$11,086
Net income	463	215	689	423
Other comprehensive income (loss)	3	-11	8	-29
Contributions from noncontrolling interests				238
Transfer of assets to Capistrano Wind Partners				-21
Common stock dividends declared			-330	-318
Dividends, distributions to noncontrolling interests and other			-75	-68
Stock-based compensation and other			-40	-45
Noncash stock-based compensation and other			12	25
Issuance of preference stock			387	804
Redemption of preference stock			-400	-75
Balance, at the end of the period	11,442	12,020	11,442	12,020
Dividends declared per common share (in dollars per share)	$0.34	$0.33	$1.01	$0.98
Common Stock Including Additional Paid in Capital [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period			2,373	2,360
Net income			0	0
Other comprehensive income (loss)			0	0
Contributions from noncontrolling interests				0
Transfer of assets to Capistrano Wind Partners				-21
Common stock dividends declared			0	0
Dividends, distributions to noncontrolling interests and other			0	0
Stock-based compensation and other			5	19
Noncash stock-based compensation and other			19	27
Issuance of preference stock			0	0
Redemption of preference stock			0	0
Balance, at the end of the period	2,397	2,385	2,397	2,385
Accumulated Other Comprehensive Loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period			-87	-139
Net income			0	0
Other comprehensive income (loss)			8	-29
Contributions from noncontrolling interests				0
Transfer of assets to Capistrano Wind Partners				0
Common stock dividends declared			0	0
Dividends, distributions to noncontrolling interests and other			0	0
Stock-based compensation and other			0	0
Noncash stock-based compensation and other			0	0
Issuance of preference stock			0	0
Redemption of preference stock			0	0
Balance, at the end of the period	-79	-168	-79	-168
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period			7,146	7,834
Net income			614	357
Other comprehensive income (loss)			0	0
Contributions from noncontrolling interests				0
Transfer of assets to Capistrano Wind Partners				0
Common stock dividends declared			-330	-318
Dividends, distributions to noncontrolling interests and other			0	0
Stock-based compensation and other			-45	-64
Noncash stock-based compensation and other			-6	-2
Issuance of preference stock			0	0
Redemption of preference stock			-8	-1
Balance, at the end of the period	7,371	7,806	7,371	7,806
Subtotal
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period			9,432	10,055
Net income			614	357
Other comprehensive income (loss)			8	-29
Contributions from noncontrolling interests				0
Transfer of assets to Capistrano Wind Partners				-21
Common stock dividends declared			-330	-318
Dividends, distributions to noncontrolling interests and other			0	0
Stock-based compensation and other			-40	-45
Noncash stock-based compensation and other			13	25
Issuance of preference stock			0	0
Redemption of preference stock			-8	-1
Balance, at the end of the period	9,689	10,023	9,689	10,023
Other Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period				2
Net income				0
Other comprehensive income (loss)				0
Contributions from noncontrolling interests				238
Transfer of assets to Capistrano Wind Partners				0
Common stock dividends declared				0
Dividends, distributions to noncontrolling interests and other				-2
Stock-based compensation and other				0
Noncash stock-based compensation and other				0
Issuance of preference stock				0
Redemption of preference stock				0
Balance, at the end of the period		238		238
Preferred Stock and Preference Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period			1,759	1,029
Net income			75	66
Other comprehensive income (loss)			0	0
Contributions from noncontrolling interests				0
Transfer of assets to Capistrano Wind Partners				0
Common stock dividends declared			0	0
Dividends, distributions to noncontrolling interests and other			-75	-66
Stock-based compensation and other			0	0
Noncash stock-based compensation and other			-1	0
Issuance of preference stock			387	804
Redemption of preference stock			-392	-74
Balance, at the end of the period	1,753	1,759	1,753	1,759
Southern California Edison
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period			11,743	9,958
Net income	502	388	717	802
Other comprehensive income (loss)	2	1	1	1
Common stock dividends declared			-360	-349
Dividends declared on preferred and preference stock			-75	-66
Stock-based compensation and other			-36	-24
Noncash stock-based compensation and other			14	13
Issuance of preference stock			387	804
Redemption of preference stock			-400	-75
Balance, at the end of the period	11,991	11,064	11,991	11,064
Southern California Edison | Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period			2,168	2,168
Net income			0	0
Other comprehensive income (loss)			0	0
Common stock dividends declared			0	0
Dividends declared on preferred and preference stock			0	0
Stock-based compensation and other			0	0
Noncash stock-based compensation and other			0	0
Issuance of preference stock			0	0
Redemption of preference stock			0	0
Balance, at the end of the period	2,168	2,168	2,168	2,168
Southern California Edison | Additional Paid-in Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period			581	596
Net income			0	0
Other comprehensive income (loss)			0	0
Common stock dividends declared			0	0
Dividends declared on preferred and preference stock			0	0
Stock-based compensation and other			3	11
Noncash stock-based compensation and other			10	13
Issuance of preference stock			-13	-21
Redemption of preference stock			8	1
Balance, at the end of the period	589	600	589	600
Southern California Edison | Accumulated Other Comprehensive Loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period			-29	-24
Net income			0	0
Other comprehensive income (loss)			1	1
Common stock dividends declared			0	0
Dividends declared on preferred and preference stock			0	0
Stock-based compensation and other			0	0
Noncash stock-based compensation and other			0	0
Issuance of preference stock			0	0
Redemption of preference stock			0	0
Balance, at the end of the period	-28	-23	-28	-23
Southern California Edison | Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period			7,228	6,173
Net income			717	802
Other comprehensive income (loss)			0	0
Common stock dividends declared			-360	-349
Dividends declared on preferred and preference stock			-75	-66
Stock-based compensation and other			-39	-35
Noncash stock-based compensation and other			4	0
Issuance of preference stock			0	0
Redemption of preference stock			-8	-1
Balance, at the end of the period	7,467	6,524	7,467	6,524
Southern California Edison | Preferred Stock and Preference Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period			1,795	1,045
Net income			0	0
Other comprehensive income (loss)			0	0
Common stock dividends declared			0	0
Dividends declared on preferred and preference stock			0	0
Stock-based compensation and other			0	0
Noncash stock-based compensation and other			0	0
Issuance of preference stock			400	825
Redemption of preference stock			-400	-75
Balance, at the end of the period	$1,795	$1,795	$1,795	$1,795

Variable_Interest_Entities_Det

Variable Interest Entities (Details) (Southern California Edison, USD $)

3 Months Ended

9 Months Ended

1 Months Ended

3 Months Ended

9 Months Ended

1 Months Ended

3 Months Ended

3 Months Ended

9 Months Ended

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Dec. 31, 2012

31-May-12

31-May-12

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2012

31-May-12

Sep. 30, 2013

Sep. 30, 2013

Jan. 31, 2013

Jan. 31, 2013

Sep. 30, 2013

Mar. 31, 2013

Sep. 30, 2013

Jan. 31, 2013

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

SCE Trust I

SCE Trust I

SCE Trust I

SCE Trust I

SCE Trust I

SCE Trust I

SCE Trust I

SCE Trust I

SCE Trust I

SCE Trust I

SCE Trust I

SCE Trust I

SCE Trust II

SCE Trust II

SCE Trust II

SCE Trust II

SCE Trust II

SCE Trust II

SCE Trust II

SCE Trust II

Variable Interest Entity, Not Primary Beneficiary

Variable Interest Entity, Not Primary Beneficiary

Variable Interest Entity, Not Primary Beneficiary

Variable Interest Entity, Not Primary Beneficiary

Trust Securities

Trust Securities

Trust Securities

Series F Preferred Stock

Series F Preferred Stock

Series F Preferred Stock

Trust Securities

Trust Securities

Series G Preferred Stock

Series G Preferred Stock

Series G Preferred Stock

SCE Power Purchase Contracts

SCE Power Purchase Contracts

SCE Power Purchase Contracts

SCE Power Purchase Contracts

MW

MW

MW

MW

Details of projects or entities

Power generating capacity (in megawatts)

5,290

2,094

5,290

2,094

Payments to unconsolidated VIEs for power purchase contracts

$330,000,000

$158,000,000

$527,000,000

$292,000,000

Unconsolidated Trust

Liquidation preference

475,000,000

400,000,000

Security dividend rate, (as a percent)

5.63%

5.10%

5.10%

Liquidation value (in dollars per share)

$25

$2,500

$25

$2,500

$2,500

Common stock

10,000

10,000

10,000

10,000

10,000

10,000

10,000

Common stock, percentage issued to Southern California Edison

100.00%

100.00%

Preference stock

475,000,000

475,000,000

475,000,000

475,000,000

475,000,000

400,000,000

400,000,000

400,000,000

Dividend income and distributions

$7,000,000

$7,000,000

$20,000,000

$10,000,000

$5,000,000

$14,000,000

Fair_Value_Measurements_Fair_V

Fair Value Measurements (Fair Value by Level) (Details) (USD $)	Sep. 30, 2013		Jun. 30, 2013	Dec. 31, 2012		Sep. 30, 2012	Jun. 30, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
Assets at Fair Value
Money market funds	$518			$107
Nuclear decommissioning trusts	4,332			4,048
Liabilities at Fair Value
Receivables (payables) net related to investments	-3			-1
Level 3
Assets at Fair Value
Total assets	253			221
Liabilities at Fair Value
Total liabilities	1,284			1,012
Southern California Edison
Assets at Fair Value
Money market funds	453			5
Nuclear decommissioning trusts	4,332		4,182	4,048		3,997	3,810	3,592
Liabilities at Fair Value
Percentage of equity investments located in the United States (as a percent)	69.00%			66.00%
Collateralized mortgage obligations and other asset backed securities	32			56
Receivables (payables) net related to investments	-3			-1
Southern California Edison | Fair Value, Measurements, Recurring | Level 1
Assets at Fair Value
Money market funds	453			5
Mutual funds	29
Derivative contracts	0			0
Long-term disability plan	8			8
Nuclear decommissioning trusts	3,172			2,869
Total assets	3,662			2,882
Liabilities at Fair Value
Derivative contracts	0			0
Total liabilities	0			0
Net assets (liabilities)	3,662			2,882
Southern California Edison | Fair Value, Measurements, Recurring | Level 1 | Stocks
Assets at Fair Value
Nuclear decommissioning trusts	2,027	[1]		2,271	[1]
Southern California Edison | Fair Value, Measurements, Recurring | Level 1 | U.S. government and agency securities
Assets at Fair Value
Nuclear decommissioning trusts	823			477
Southern California Edison | Fair Value, Measurements, Recurring | Level 1 | Municipal bonds
Assets at Fair Value
Nuclear decommissioning trusts	0			0
Southern California Edison | Fair Value, Measurements, Recurring | Level 1 | Corporate bonds
Assets at Fair Value
Nuclear decommissioning trusts	0	[2]		0	[2]
Southern California Edison | Fair Value, Measurements, Recurring | Level 1 | Short-term investments, primarily cash equivalents
Assets at Fair Value
Nuclear decommissioning trusts	322	[3]		121	[3]
Southern California Edison | Fair Value, Measurements, Recurring | Level 1 | Congestion Revenue Rights
Assets at Fair Value
Derivative contracts	0			0
Southern California Edison | Fair Value, Measurements, Recurring | Level 1 | Electricity
Assets at Fair Value
Derivative contracts	0			0
Liabilities at Fair Value
Derivative contracts	0			0
Southern California Edison | Fair Value, Measurements, Recurring | Level 1 | Natural Gas
Assets at Fair Value
Derivative contracts	0			0
Liabilities at Fair Value
Derivative contracts	0			0
Southern California Edison | Fair Value, Measurements, Recurring | Level 1 | Tolling
Assets at Fair Value
Derivative contracts	0			0
Liabilities at Fair Value
Derivative contracts	0			0
Southern California Edison | Fair Value, Measurements, Recurring | Level 2
Assets at Fair Value
Money market funds	0			0
Mutual funds	0
Derivative contracts	2			8
Long-term disability plan	0			0
Nuclear decommissioning trusts	1,163			1,180
Total assets	1,165			1,188
Liabilities at Fair Value
Derivative contracts	48			115
Total liabilities	48			115
Net assets (liabilities)	1,117			1,073
Southern California Edison | Fair Value, Measurements, Recurring | Level 2 | Stocks
Assets at Fair Value
Nuclear decommissioning trusts	0	[1]		0	[1]
Southern California Edison | Fair Value, Measurements, Recurring | Level 2 | U.S. government and agency securities
Assets at Fair Value
Nuclear decommissioning trusts	101			126
Southern California Edison | Fair Value, Measurements, Recurring | Level 2 | Municipal bonds
Assets at Fair Value
Nuclear decommissioning trusts	796			644
Southern California Edison | Fair Value, Measurements, Recurring | Level 2 | Corporate bonds
Assets at Fair Value
Nuclear decommissioning trusts	221	[2]		410	[2]
Southern California Edison | Fair Value, Measurements, Recurring | Level 2 | Short-term investments, primarily cash equivalents
Assets at Fair Value
Nuclear decommissioning trusts	45	[3]		0	[3]
Southern California Edison | Fair Value, Measurements, Recurring | Level 2 | Congestion Revenue Rights
Assets at Fair Value
Derivative contracts	0			0
Southern California Edison | Fair Value, Measurements, Recurring | Level 2 | Electricity
Assets at Fair Value
Derivative contracts	1			0
Liabilities at Fair Value
Derivative contracts	5			2
Southern California Edison | Fair Value, Measurements, Recurring | Level 2 | Natural Gas
Assets at Fair Value
Derivative contracts	1			8
Liabilities at Fair Value
Derivative contracts	43			113
Southern California Edison | Fair Value, Measurements, Recurring | Level 2 | Tolling
Assets at Fair Value
Derivative contracts	0			0
Liabilities at Fair Value
Derivative contracts	0			0
Southern California Edison | Fair Value, Measurements, Recurring | Level 3
Assets at Fair Value
Money market funds	0			0
Mutual funds	0
Derivative contracts	253			221
Long-term disability plan	0			0
Nuclear decommissioning trusts	0			0
Total assets	253			221
Liabilities at Fair Value
Derivative contracts	1,284			1,012
Total liabilities	1,284			1,012
Net assets (liabilities)	-1,031			-791
Southern California Edison | Fair Value, Measurements, Recurring | Level 3 | Stocks
Assets at Fair Value
Nuclear decommissioning trusts	0	[1]		0	[1]
Southern California Edison | Fair Value, Measurements, Recurring | Level 3 | U.S. government and agency securities
Assets at Fair Value
Nuclear decommissioning trusts	0			0
Southern California Edison | Fair Value, Measurements, Recurring | Level 3 | Municipal bonds
Assets at Fair Value
Nuclear decommissioning trusts	0			0
Southern California Edison | Fair Value, Measurements, Recurring | Level 3 | Corporate bonds
Assets at Fair Value
Nuclear decommissioning trusts	0	[2]		0	[2]
Southern California Edison | Fair Value, Measurements, Recurring | Level 3 | Short-term investments, primarily cash equivalents
Assets at Fair Value
Nuclear decommissioning trusts	0	[3]		0	[3]
Southern California Edison | Fair Value, Measurements, Recurring | Level 3 | Congestion Revenue Rights
Assets at Fair Value
Derivative contracts	245			186
Southern California Edison | Fair Value, Measurements, Recurring | Level 3 | Electricity
Assets at Fair Value
Derivative contracts	0			31
Liabilities at Fair Value
Derivative contracts	12			5
Southern California Edison | Fair Value, Measurements, Recurring | Level 3 | Natural Gas
Assets at Fair Value
Derivative contracts	0			0
Liabilities at Fair Value
Derivative contracts	0			2
Southern California Edison | Fair Value, Measurements, Recurring | Level 3 | Tolling
Assets at Fair Value
Derivative contracts	8			4
Liabilities at Fair Value
Derivative contracts	1,272			1,005
Southern California Edison | Fair Value, Measurements, Recurring | Netting and Collateral
Assets at Fair Value
Money market funds	0	[4]		0	[4]
Mutual funds	0
Derivative contracts	-1	[4]		-15	[4]
Long-term disability plan	0	[4]		0	[4]
Nuclear decommissioning trusts	0	[4]		0	[4]
Total assets	-1	[4]		-15	[4]
Liabilities at Fair Value
Derivative contracts	-21	[4]		-62	[4]
Total liabilities	-21	[4]		-62	[4]
Net assets (liabilities)	20	[4]		47	[4]
Southern California Edison | Fair Value, Measurements, Recurring | Netting and Collateral | Stocks
Assets at Fair Value
Nuclear decommissioning trusts	0	[1],[4]		0	[1],[4]
Southern California Edison | Fair Value, Measurements, Recurring | Netting and Collateral | U.S. government and agency securities
Assets at Fair Value
Nuclear decommissioning trusts	0	[4]		0	[4]
Southern California Edison | Fair Value, Measurements, Recurring | Netting and Collateral | Municipal bonds
Assets at Fair Value
Nuclear decommissioning trusts	0	[4]		0	[4]
Southern California Edison | Fair Value, Measurements, Recurring | Netting and Collateral | Corporate bonds
Assets at Fair Value
Nuclear decommissioning trusts	0	[2],[4]		0	[2],[4]
Southern California Edison | Fair Value, Measurements, Recurring | Netting and Collateral | Short-term investments, primarily cash equivalents
Assets at Fair Value
Nuclear decommissioning trusts	0	[3],[4]		0	[3],[4]
Southern California Edison | Fair Value, Measurements, Recurring | Netting and Collateral | Congestion Revenue Rights
Assets at Fair Value
Derivative contracts	0	[4]		0	[4]
Southern California Edison | Fair Value, Measurements, Recurring | Netting and Collateral | Electricity
Assets at Fair Value
Derivative contracts	0	[4]		-13	[4]
Liabilities at Fair Value
Derivative contracts	-3	[4]		-2	[4]
Southern California Edison | Fair Value, Measurements, Recurring | Netting and Collateral | Natural Gas
Assets at Fair Value
Derivative contracts	-1	[4]		-2	[4]
Liabilities at Fair Value
Derivative contracts	-18	[4]		-60	[4]
Southern California Edison | Fair Value, Measurements, Recurring | Netting and Collateral | Tolling
Assets at Fair Value
Derivative contracts	0	[4]		0	[4]
Liabilities at Fair Value
Derivative contracts	0	[4]		0	[4]
Southern California Edison | Fair Value, Measurements, Recurring | Total
Assets at Fair Value
Money market funds	453			5
Mutual funds	29
Derivative contracts	254			214
Long-term disability plan	8			8
Nuclear decommissioning trusts	4,335			4,049
Total assets	5,079			4,276
Liabilities at Fair Value
Derivative contracts	1,311			1,065
Total liabilities	1,311			1,065
Net assets (liabilities)	3,768			3,211
Southern California Edison | Fair Value, Measurements, Recurring | Total | Stocks
Assets at Fair Value
Nuclear decommissioning trusts	2,027	[1]		2,271	[1]
Southern California Edison | Fair Value, Measurements, Recurring | Total | U.S. government and agency securities
Assets at Fair Value
Nuclear decommissioning trusts	924			603
Southern California Edison | Fair Value, Measurements, Recurring | Total | Municipal bonds
Assets at Fair Value
Nuclear decommissioning trusts	796			644
Southern California Edison | Fair Value, Measurements, Recurring | Total | Corporate bonds
Assets at Fair Value
Nuclear decommissioning trusts	221	[2]		410	[2]
Southern California Edison | Fair Value, Measurements, Recurring | Total | Short-term investments, primarily cash equivalents
Assets at Fair Value
Nuclear decommissioning trusts	367	[3]		121	[3]
Southern California Edison | Fair Value, Measurements, Recurring | Total | Congestion Revenue Rights
Assets at Fair Value
Derivative contracts	245			186
Southern California Edison | Fair Value, Measurements, Recurring | Total | Electricity
Assets at Fair Value
Derivative contracts	1			18
Liabilities at Fair Value
Derivative contracts	14			5
Southern California Edison | Fair Value, Measurements, Recurring | Total | Natural Gas
Assets at Fair Value
Derivative contracts	0			6
Liabilities at Fair Value
Derivative contracts	25			55
Southern California Edison | Fair Value, Measurements, Recurring | Total | Tolling
Assets at Fair Value
Derivative contracts	8			4
Liabilities at Fair Value
Derivative contracts	$1,272			$1,005
[1]	Approximately 69% and 66% of SCE's equity investments were located in the United States at SeptemberB 30, 2013 and DecemberB 31, 2012, respectively.
[2]	At SeptemberB 30, 2013 and DecemberB 31, 2012, SCE's corporate bonds were diversified and included collateralized mortgage obligations and other asset backed securities of $32 million and $56 million, respectively.
[3]	Excludes net payables of $3 million and $1 million at SeptemberB 30, 2013 and DecemberB 31, 2012, respectively, of interest and dividend receivables as well as receivables and payables related to SCE's pending securities sales and purchases.
[4]	Represents the netting of assets and liabilities under master netting agreements and cash collateral across the levels of the fair value hierarchy. Netting among positions classified within the same level is included in that level.

Fair_Value_Measurements_Level_

Fair Value Measurements (Level 3 Rollforward) (Details) (Southern California Edison, Level 3, USD $)	3 Months Ended				9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Southern California Edison | Level 3
Fair Value Disclosures Level 3 [Roll Forward]
Fair value of net asset (liabilities) at beginning of period	($967)		($739)		($791)		($754)
Total realized/unrealized gains (losses):
Included in regulatory assets and liabilities	-50	[1]	-180	[1]	-205	[1]	-203	[1]
Purchases	19		33		56		84
Settlements	-33		-44		-91		-57
Fair value of net liabilities at end of period	-1,031		-930		-1,031		-930
Change during the period in unrealized losses related to assets and liabilities held at the end of the period	($65)		($222)		($198)		($244)
[1]	Due to regulatory mechanisms, SCE's realized and unrealized gains and losses are recorded as regulatory assets and liabilities.

Fair_Value_Measurements_Quanti

Fair Value Measurements (Quantitative Information About Level 3 Fair Value Measurements) (Details) (Level 3, USD $)	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Quantitative Information About Level 3 Measurements [Line Items]
Fair Value, Assets	$253,000,000	$221,000,000
Fair Value, Liabilities	1,284,000,000	1,012,000,000
Electricity Options | Option Model
Quantitative Information About Level 3 Measurements [Line Items]
Fair Value, Assets	2,000,000	40,000,000
Fair Value, Liabilities	10,000,000	12,000,000
Electricity Options | Option Model | Power Prices | Minimum
Quantitative Information About Level 3 Measurements [Line Items]
Expected volatility rate (as a percent)	28.00%	29.00%
Expected prices (in dollars per unit)	40.6	41.7
Electricity Options | Option Model | Power Prices | Maximum
Quantitative Information About Level 3 Measurements [Line Items]
Expected volatility rate (as a percent)	45.00%	64.00%
Expected prices (in dollars per unit)	49.8	59.2
Electricity Options | Option Model | Power Prices | Weighted Average
Quantitative Information About Level 3 Measurements [Line Items]
Expected volatility rate (as a percent)	39.00%	42.00%
Expected prices (in dollars per unit)	43.5	47
Electricity Options | Option Model | Gas Prices | Minimum
Quantitative Information About Level 3 Measurements [Line Items]
Expected volatility rate (as a percent)	24.00%	25.00%
Electricity Options | Option Model | Gas Prices | Maximum
Quantitative Information About Level 3 Measurements [Line Items]
Expected volatility rate (as a percent)	30.00%	36.00%
Electricity Options | Option Model | Gas Prices | Weighted Average
Quantitative Information About Level 3 Measurements [Line Items]
Expected volatility rate (as a percent)	28.00%	33.00%
Electricity Forwards | Discounted Cash Flow
Quantitative Information About Level 3 Measurements [Line Items]
Fair Value, Assets	0	2,000,000
Fair Value, Liabilities	4,000,000	4,000,000
Electricity Forwards | Discounted Cash Flow | Power Prices | Minimum
Quantitative Information About Level 3 Measurements [Line Items]
Expected prices (in dollars per unit)	7.7	23.1
Electricity Forwards | Discounted Cash Flow | Power Prices | Maximum
Quantitative Information About Level 3 Measurements [Line Items]
Expected prices (in dollars per unit)	40.8	44.9
Electricity Forwards | Discounted Cash Flow | Power Prices | Weighted Average
Quantitative Information About Level 3 Measurements [Line Items]
Expected prices (in dollars per unit)	31.4	31.1
Congestion Revenue Rights | Market Simulation Model
Quantitative Information About Level 3 Measurements [Line Items]
Fair Value, Assets	245,000,000	186,000,000
Fair Value, Liabilities	0	0
Congestion Revenue Rights | Market Simulation Model | Load Forecast | Minimum
Quantitative Information About Level 3 Measurements [Line Items]
Fair value inputs, power units (in megawatts)	7,603	7,597
Congestion Revenue Rights | Market Simulation Model | Load Forecast | Maximum
Quantitative Information About Level 3 Measurements [Line Items]
Fair value inputs, power units (in megawatts)	24,896	26,612
Congestion Revenue Rights | Market Simulation Model | Power Prices | Minimum
Quantitative Information About Level 3 Measurements [Line Items]
Expected prices (in dollars per unit)	-9.86	-13.9
Congestion Revenue Rights | Market Simulation Model | Power Prices | Maximum
Quantitative Information About Level 3 Measurements [Line Items]
Expected prices (in dollars per unit)	108.56	226.75
Congestion Revenue Rights | Market Simulation Model | Gas Prices | Minimum
Quantitative Information About Level 3 Measurements [Line Items]
Expected prices (in dollars per unit)	3.5	2.95
Congestion Revenue Rights | Market Simulation Model | Gas Prices | Maximum
Quantitative Information About Level 3 Measurements [Line Items]
Expected prices (in dollars per unit)	7.1	7.78
Gas Options | Option Model
Quantitative Information About Level 3 Measurements [Line Items]
Fair Value, Assets		0
Fair Value, Liabilities		2,000,000
Gas Options | Option Model | Gas Prices | Minimum
Quantitative Information About Level 3 Measurements [Line Items]
Expected volatility rate (as a percent)		28.00%
Gas Options | Option Model | Gas Prices | Maximum
Quantitative Information About Level 3 Measurements [Line Items]
Expected volatility rate (as a percent)		36.00%
Gas Options | Option Model | Gas Prices | Weighted Average
Quantitative Information About Level 3 Measurements [Line Items]
Expected volatility rate (as a percent)		34.00%
Tolling | Option Model
Quantitative Information About Level 3 Measurements [Line Items]
Fair Value, Assets	8,000,000	4,000,000
Fair Value, Liabilities	1,272,000,000	1,005,000,000
Tolling | Option Model | Power Prices | Minimum
Quantitative Information About Level 3 Measurements [Line Items]
Expected volatility rate (as a percent)	25.00%	26.00%
Expected prices (in dollars per unit)	35.9	35
Tolling | Option Model | Power Prices | Maximum
Quantitative Information About Level 3 Measurements [Line Items]
Expected volatility rate (as a percent)	45.00%	64.00%
Expected prices (in dollars per unit)	62.6	84.1
Tolling | Option Model | Power Prices | Weighted Average
Quantitative Information About Level 3 Measurements [Line Items]
Expected volatility rate (as a percent)	29.00%	29.00%
Expected prices (in dollars per unit)	46.9	55.4
Tolling | Option Model | Gas Prices | Minimum
Quantitative Information About Level 3 Measurements [Line Items]
Expected volatility rate (as a percent)	16.00%	17.00%
Tolling | Option Model | Gas Prices | Maximum
Quantitative Information About Level 3 Measurements [Line Items]
Expected volatility rate (as a percent)	30.00%	36.00%
Tolling | Option Model | Gas Prices | Weighted Average
Quantitative Information About Level 3 Measurements [Line Items]
Expected volatility rate (as a percent)	19.00%	22.00%
Netting
Quantitative Information About Level 3 Measurements [Line Items]
Fair Value, Assets	-2,000,000	-11,000,000
Fair Value, Liabilities	($2,000,000)	($11,000,000)

Fair_Value_Measurements_Fair_V1

Fair Value Measurements (Fair Value of Long-Term Debt Recorded at Carrying Value) (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Fair Value of Long-Term Debt Recorded at Carrying Value
Carrying Value	$9,232	$9,231
Fair Value	10,016	10,944
Southern California Edison
Fair Value of Long-Term Debt Recorded at Carrying Value
Carrying Value	8,828	8,828
Fair Value	$9,590	$10,505

Debt_and_Credit_Agreements_Det

Debt and Credit Agreements (Details) (USD $)

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2012

Mar. 31, 2013

Jul. 18, 2013

Jul. 18, 2013

Sep. 30, 2013

Jul. 18, 2013

Dec. 31, 2012

Jul. 18, 2013

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Oct. 31, 2013

Oct. 31, 2013

Oct. 31, 2013

Oct. 31, 2013

In Millions, unless otherwise specified

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

Edison International Parent and Other

Edison International Parent and Other

Edison International Parent and Other

Edison International Parent and Other

Commercial paper

Commercial paper

Letters of credit

Subsequent Event

Subsequent Event

Subsequent Event

Subsequent Event

3.90% First and refunding mortgage bonds due 2043

Revolving credit facility

Credit facility maturing in July 2018

Revolving credit facility

Revolving credit facility

Revolving credit facility

Credit facility maturing in July 2018

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

Revolving credit facility

Revolving credit facility

Revolving credit facility

First and refunding mortgage bonds

3.50% First and refunding mortgage bonds due 2023

4.65% First and refunding mortgage bonds due 2043

Floating rate bonds due 2014

Debt Instrument [Line Items]

Issuance of debt

$400

$600

$800

$200

Stated interest rate (as a percent)

3.90%

3.50%

4.65%

Extinguishment of Debt, Amount

800

Outstanding borrowings

1,350

175

Weighted average interest rate (as a percent)

1.46%

0.25%

0.37%

Commitment

150

2,600

1,250

68

1,182

2,750

Outstanding letters of credit

140

Letters of credit expiration period

12 months

Short-term debt

$1,528

$175

$1,354

$175

$174

$0

Derivative_Instruments_Balance

Derivative Instruments (Balance Sheet Disclosures) (Details) (USD $)	Sep. 30, 2013		Dec. 31, 2012
In Millions, unless otherwise specified
Fair Value of Derivative Instruments
Short-Term, Derivative Assets	$47		$129
Long-Term, Derivative Assets	207		85
Short-Term, Derivative Liabilities	174		126
Long-Term, Derivative Liabilities	1,137		939
Southern California Edison
Fair Value of Derivative Instruments
Short-Term, Derivative Assets	47		129
Long-Term, Derivative Assets	207		85
Short-Term, Derivative Liabilities	174		126
Long-Term, Derivative Liabilities	1,137		939
Southern California Edison | Commodity Contracts | Electric Utility
Fair Value of Derivative Instruments
Short-Term, Derivative Assets	47		129
Long-Term, Derivative Assets	207		85
Derivative Assets, Total	254		214
Short-Term, Derivative Liabilities	174		126
Long-Term, Derivative Liabilities	1,137		939
Derivative Liabilities, Total	1,311		1,065
Net Liability	1,057		851
Southern California Edison | Commodity Contracts | Electric Utility | Economic hedges
Fair Value of Derivative Instruments
Short-Term, Derivative Assets	53		151
Long-Term, Derivative Assets	207		91
Derivative Assets, Total	260		242
Short-Term, Derivative Liabilities	195		186
Long-Term, Derivative Liabilities	1,143		954
Derivative Liabilities, Total	1,338		1,140
Net Liability	1,078		898
Southern California Edison | Commodity Contracts | Electric Utility | Netting and Collateral
Fair Value of Derivative Instruments
Short-Term, Derivative Assets	-6		-22
Long-Term, Derivative Assets	0		-6
Derivative Assets, Total	-6		-28
Short-Term, Derivative Liabilities	-6		-22
Long-Term, Derivative Liabilities	0		-6
Derivative Liabilities, Total	-6		-28
Net Liability	0		0
Southern California Edison | Commodity Contracts | Electric Utility | Cash Collateral Posted
Fair Value of Derivative Instruments
Short-Term, Derivative Assets	0	[1]	0	[1]
Long-Term, Derivative Assets	0	[1]	0	[1]
Derivative Assets, Total	0	[1]	0	[1]
Short-Term, Derivative Liabilities	-15	[1]	-38	[1]
Long-Term, Derivative Liabilities	-6	[1]	-9	[1]
Derivative Liabilities, Total	-21	[1]	-47	[1]
Net Liability	($21)	[1]	($47)	[1]
[1]	In addition, at SeptemberB 30, 2013 and DecemberB 31, 2012, SCE had posted $14 million and $8 million, respectively, of collateral that is not offset against the derivative liabilities and is reflected in "Other current assets" on the consolidated balance sheets.

Derivative_Instruments_Notiona

Derivative Instruments (Notional Values) (Details) (Southern California Edison, Electric Utility, Economic hedges)	Sep. 30, 2013	Dec. 31, 2012
	GWh	GWh
Electricity options, swaps and forwards (GWh)
Derivatives
Notional volumes of derivative instruments	8,964	15,884
Natural gas options, swaps and forwards (Bcf)
Derivatives
Notional volumes of derivative instruments	12	100
Congestion revenue rights (GWh)
Derivatives
Notional volumes of derivative instruments	127,772	149,774
Tolling arrangements (GWh)
Derivatives
Notional volumes of derivative instruments	97,893	101,485

Derivative_Instruments_Additio

Derivative Instruments (Additional Disclosures) (Details) (Southern California Edison, USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Electric Utility | Economic hedges
Derivatives
Realized losses	($15)	($77)	($38)	($199)
Unrealized losses	-41	-91	-159	-29
Aggregate fair value of all derivative liabilities with credit-risk-related contingent features	53		53		6
Additional collateral, aggregate fair value	14		14
Collateral already posted	0		0		0
Other current assets | Commodity Contracts
Derivatives
Collateral already posted	$14		$14		$8

Income_Taxes_Tax_Rate_Reconcil

Income Taxes (Tax Rate Reconciliation) (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Effective Tax Rate
Income (loss) from continuing operations before income taxes	$665	$610	$863	$1,204
Provision for income tax at federal statutory rate of 35%	233	214	302	421
State tax, net of federal benefit	22	46	5	60
Property-related	-57	-20	-121	-39
Uncertain tax positions	-5	1	13	2
Other	-16	-13	-26	-23
Total income tax expense (benefit) from continuing operations	177	228	173	421
Federal statutory rate (as a percent)	35.00%	35.00%	35.00%	35.00%
Effective tax rate	26.60%	37.40%	20.00%	35.00%
Southern California Edison
Effective Tax Rate
Income (loss) from continuing operations before income taxes	685	564	913	1,186
Provision for income tax at federal statutory rate of 35%	240	197	319	415
State tax, net of federal benefit	21	10	12	30
Property-related	-57	-19	-121	-39
Uncertain tax positions	-6	1	11	1
Other	-15	-13	-25	-23
Total income tax expense (benefit) from continuing operations	$183	$176	$196	$384
Federal statutory rate (as a percent)	35.00%	35.00%	35.00%	35.00%
Effective tax rate	26.70%	31.20%	21.50%	32.40%

Income_Taxes_Textual_Details

Income Taxes (Textual) (Details) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013
Income Tax Disclosure [Line Items]
Operating Loss Carryforwards	$1,300
Income tax expense from discontinued operations	25
IRS Examination
Income Tax Disclosure [Line Items]
Estimated potential future federal tax payment as of the balance sheet date, including interest and penalties, based on a proposed adjustment	205
Penalty for understatement of tax liability (as a percent)	40.00%
Southern California Edison
Income Tax Disclosure [Line Items]
Estimated federal tax payment as a result of the proposed adjustment to adjust repair allowance deduction	74
Operating Loss Carryforwards	177
Southern California Edison | IRS Examination
Income Tax Disclosure [Line Items]
Estimated potential future federal tax payment as of the balance sheet date, including interest and penalties, based on a proposed adjustment	99
General Business Tax Credit Carryforward [Member] | IRS Examination
Income Tax Disclosure [Line Items]
Tax Credit Carryforward, Amount	311
General Business Tax Credit Carryforward [Member] | Southern California Edison | IRS Examination
Income Tax Disclosure [Line Items]
Tax Credit Carryforward, Amount	44
2029-2032 | General Business Tax Credit Carryforward [Member] | IRS Examination
Income Tax Disclosure [Line Items]
Tax Credit Carryforwards, Subject to Expiration	289
2015-2024
Income Tax Disclosure [Line Items]
Operating Loss Carryforwards, Subject to Expiration	32
2030-2032 | General Business Tax Credit Carryforward [Member] | Southern California Edison | IRS Examination
Income Tax Disclosure [Line Items]
Tax Credit Carryforwards, Subject to Expiration	30
2015-2016 | Southern California Edison
Income Tax Disclosure [Line Items]
Operating Loss Carryforwards, Subject to Expiration	$18

Compensation_and_Benefit_Plans2

Compensation and Benefit Plans (Expense Components) (Details) (USD $)	3 Months Ended				9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Postretirement Benefits Other Than Pensions
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	$14		$13		$42		$37
Interest cost	26		28		78		85
Expected return on plan assets	-30		-27		-90		-81
Special termination benefits	0	[1]	3	[1]	10	[1]	3	[1]
Amortization of prior service cost	-9		-9		-27		-27
Amortization of net loss	7	[2]	12	[2]	21	[2]	35	[2]
Expense under accounting standards	8		20		34		52
Pension Plans
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	38		44		114		121
Interest cost	42		46		126		137
Expected return on plan assets	-58		-53		-172		-164
Settlement costs	24	[3]	1	[3]	73	[3]	4	[3]
Amortization of prior service cost	1		1		3		3
Amortization of net loss	15	[4]	18	[4]	45	[4]	48	[4]
Expense under accounting standards	62		57		189		149
Regulatory adjustment (deferred)	-7		-57		-21		-3
Total expense recognized	55		0		168		146
Net loss reclassified	4				11
Net loss reclassified, settlement costs					2
Southern California Edison | Postretirement Benefits Other Than Pensions
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	14		12		41		36
Interest cost	26		28		78		84
Expected return on plan assets	-30		-27		-90		-81
Special termination benefits	0	[1]	3	[1]	10	[1]	3	[1]
Amortization of prior service cost	-9		-9		-27		-27
Amortization of net loss	7	[2]	11	[2]	21	[2]	33	[2]
Expense under accounting standards	8		18		33		48
Net loss reclassified	0				0
Southern California Edison | Pension Plans
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	37		46		111		120
Interest cost	41		45		123		135
Expected return on plan assets	-57		-52		-171		-162
Settlement costs	24		1		72		3
Amortization of prior service cost	1		1		3		3
Amortization of net loss	14	[4]	14	[4]	42	[4]	42	[4]
Expense under accounting standards	60		55		180		141
Regulatory adjustment (deferred)	-7		-57		-21		-3
Total expense recognized	53		-2		159		138
Net loss reclassified	3				8
Maximum | Postretirement Benefits Other Than Pensions
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Net loss reclassified	$1				$1
[1]	Due to the reduction in workforce, SCE has incurred costs for extended retiree health care coverage.
[2]	Includes the amount of net loss reclassified from other comprehensive loss. The amount reclassified for Edison International and SCE was less than $1 million and zero for the three- and nine-months ended SeptemberB 30, 2013, respectively.
[3]	Includes the amount of net loss reclassified from other comprehensive loss. The amount reclassified for Edison International was $2B million for the nine months ended September 30, 2013.
[4]	Includes the amount of net loss reclassified from other comprehensive loss. The amount reclassified for Edison International and SCE was $4 million and $3 million for the three months ended SeptemberB 30, 2013, respectively, and $11 million and $8B million for the nine months ended September 30, 2013, respectively.

Compensation_and_Benefit_Plans3

Compensation and Benefit Plans (Workforce Reduction) (Details) (Southern California Edison, USD $)	3 Months Ended	9 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2013	Sep. 30, 2013
	positions	positions
Employee severance
Restructuring Cost and Reserve [Line Items]
Beginning balance		104
Additions		109
Payments		-132
Ending balance		81
San Onofre [Member]
Restructuring Cost and Reserve [Line Items]
San Onofre expected number of positions to be eliminated	960	960
Support Organizations, Expected Number of Positions to Be Eliminated		175

Compensation_and_Benefit_Plans4

Compensation and Benefit Plans (Textual) (Details) (USD $)

9 Months Ended

9 Months Ended

9 Months Ended

In Millions, unless otherwise specified

Sep. 30, 2013

Aug. 31, 2013

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Aug. 31, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2012

Aug. 31, 2013

31-May-13

Pension Plans

Postretirement Benefits Other Than Pensions

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

Initial

Revised

Revised

Pension Plans

Pension and Other Postretirement Benefits

Defined Benefit Plan, Actuarial Gain (Loss)

$338

$341

Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate

3.75%

4.50%

4.25%

Defined Benefit Plan, Unfunded Status of Plan

739

1,110

701

1,070

Employer contributions

175

22

163

Estimated future contributions in remainder of 2013

$13

$13

$2

Permanent_Retirement_of_San_On1

Permanent Retirement of San Onofre (Details) (USD $)

3 Months Ended

9 Months Ended

9 Months Ended

1 Months Ended

3 Months Ended

4 Months Ended

9 Months Ended

9 Months Ended

3 Months Ended

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Dec. 31, 2012

Sep. 30, 2013

Jun. 30, 2013

Sep. 30, 2013

Dec. 31, 2012

Jun. 30, 2013

Jun. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

31-May-13

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Jun. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

San Onofre (nuclear)

San Onofre (nuclear)

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

Mitsubishi Heavy Industries Ltd [Member]

Replacement Steam Generators

Supporting Ongoing Activities at the Site

Employee severance

Decommissioning Plan

Property, plant and equipment

Estimated losses on disposal of nuclear fuel inventory

Refunds of excess revenue

San Onofre (nuclear)

San Onofre (nuclear)

San Onofre (nuclear)

San Onofre (nuclear)

San Onofre (nuclear)

San Onofre (nuclear)

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

positions

invoices

positions

San Onofre (nuclear)

San Onofre (nuclear)

San Onofre (nuclear)

San Onofre (nuclear)

San Onofre (nuclear)

San Onofre (nuclear)

San Onofre (nuclear)

invoices

positions

Regulatory Assets [Line Items]

Cumulative amount of revenue collected since January 1, 2012

$1,100,000,000

$1,100,000,000

Cost of service

56,000,000

-129,000,000

Decommissioning Nuclear Facilities Net Investment

2,100,000,000

Authorized expenditures by authoritative body

525,000,000

525,000,000

Authorized expenditures by authoritative body, after adjustments for inflation

665,000,000

665,000,000

Jointly Owned Utility Plant, Proportionate Ownership Share

78.21%

78.21%

Authorized expenditures by authoritative body, spent to date

602,000,000

Authorized expenditures by authoritative body, market costs incurred

191,000,000

680,000,000

Authorized expenditures by authoritative body, Planned Outage Costs

65,000,000

Public Utilities, Incremental Inspection and Repair Costs

115,000,000

Public Utilities, Incremental Inspection and Repair Costs, Payments from Third Party

36,000,000

Amount of assets reclassified to a regulatory asset

1,521,000,000

Regulatory assets

8,015,000,000

8,015,000,000

6,422,000,000

8,015,000,000

6,422,000,000

404,000,000

Asset impairment and other

0

-66,000,000

575,000,000

-65,000,000

575,000,000

Asset impairment net of tax

365,000,000

San Onofre expected number of positions to be eliminated

960

960

175

Disposal Group, Including Discontinued Operation, Accrued Liabilities

56,000,000

Net regulatory asset

1,450,000,000

1,450,000,000

1,540,000,000

33,000,000

-129,000,000

Warranty Period

20 years

Maximum liability for purchase agreement for damages

138,000,000

Notice of intent to sue, notice time period

90 days

Number of Invoices for Reimbursement

7

7

Gain Contingency, Invoiced Amount for Reimbursement

149,000,000

149,000,000

Gain Contingency, Invoiced Amount Paid for Reimbursement

45,000,000

Notice Of Claim Amount

$390,000,000

$306,000,000

$306,000,000

Outage Policy Benefit Reduction Percentage

90.00%

Other_Investments_Amortized_Co

Other Investments (Amortized Cost and Fair Value of Nuclear Decommissioning Trusts) (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Dec. 31, 2011	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified			Southern California Edison	Southern California Edison	Southern California Edison	Southern California Edison	Southern California Edison	Southern California Edison	Southern California Edison	Southern California Edison	Southern California Edison	Southern California Edison	Southern California Edison	Southern California Edison	Southern California Edison	Southern California Edison	Southern California Edison	Southern California Edison
									Stocks	Stocks	Municipal bonds	Municipal bonds	U.S. government and agency securities	U.S. government and agency securities	Corporate bonds	Corporate bonds	Short-term investments and receivables/payables	Short-term investments and receivables/payables
Nuclear Decommissioning Trusts Disclosures
Longest Maturity Dates (in years)									0		2051		2043		2054		One-year
Total Investments, Amortized Cost			$2,724		$2,484				$635	$978	$701	$518	$861	$547	$176	$324	$351	$117
Total Investments, Fair Value			4,335		4,049				2,027	2,271	796	644	924	603	221	410	367	121
Net payables	-3	-1	-3		-1
Total Nuclear Decommissioning Trusts, Amortized Cost			2,721		2,483
Total Nuclear Decommissioning Trusts, Fair Value	$4,332	$4,048	$4,332	$4,182	$4,048	$3,997	$3,810	$3,592

Other_Investments_Summary_of_C

Other Investments (Summary of Changes in Fair Value of the Nuclear Decommissioning Trusts) (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
In Millions, unless otherwise specified			Southern California Edison	Southern California Edison	Southern California Edison	Southern California Edison
Summary Of Changes In The Fair Value [Roll Forward]
Balance at beginning of period	$4,332	$4,048	$4,182	$3,810	$4,048	$3,592
Gross realized gains			119	13	261	54
Gross realized losses			-17	0	-18	-5
Unrealized gains, net			55	156	46	272
Other-than-temporary impairments			-15	-7	-44	-30
Interest, dividends, contributions and other			8	25	39	114
Balance at end of period	$4,332	$4,048	$4,332	$3,997	$4,332	$3,997

Other_Investments_Textual_Deta

Other Investments (Textual) (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Other Investments [Line Items]
Proceeds from sale of securities			$4,574,000,000	$1,525,000,000
Southern California Edison
Other Investments [Line Items]
Contributions received for decommissioning trusts			23,000,000
Proceeds from sale of securities	2,600,000,000	428,000,000	4,574,000,000	1,525,000,000
Unrealized holding gains, net of losses	$1,600,000,000		$1,600,000,000

Regulatory_Assets_and_Liabilit2

Regulatory Assets and Liabilities (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Regulatory Assets
Regulatory Assets, Current	$506	$572
Regulatory Asset, Long-term	8,015	6,422
Regulatory Liabilities
Regulatory Liabilities, Current	629	536
Regulatory Liabilities, Long-term	4,989	5,214
Southern California Edison
Regulatory Assets
Regulatory Assets, Current	506	572
Regulatory Asset, Long-term	8,015	6,422
Total Regulatory Assets	8,521	6,994
Regulatory Liabilities
Regulatory Liabilities, Current	629	536
Regulatory Liabilities, Long-term	4,989	5,214
Total Regulatory Liabilities	5,618	5,750
Southern California Edison | Regulatory balancing accounts
Regulatory Assets
Regulatory Assets, Current	344	502
Regulatory Asset, Long-term	626	73
Southern California Edison | Energy derivatives
Regulatory Assets
Regulatory Assets, Current	162	70
Regulatory Asset, Long-term	960	900
Southern California Edison | Deferred income taxes, net
Regulatory Assets
Regulatory Asset, Long-term	2,911	2,663
Southern California Edison | Other
Regulatory Assets
Regulatory Asset, Long-term	358	360
Regulatory Liabilities
Regulatory Liabilities, Current	49	52
Regulatory Liabilities, Long-term	11	7
Southern California Edison | Pensions and other postretirement benefits
Regulatory Assets
Regulatory Asset, Long-term	1,105	1,550
Southern California Edison | Unamortized investments, net
Regulatory Assets
Regulatory Asset, Long-term	358	507
Southern California Edison | San Onofre (nuclear)
Regulatory Assets
Regulatory Asset, Long-term	1,450	0
Southern California Edison | Unamortized loss on reacquired debt
Regulatory Assets
Regulatory Asset, Long-term	213	228
Southern California Edison | Nuclear-related investment, net
Regulatory Assets
Regulatory Asset, Long-term	34	141
Southern California Edison | Regulatory balancing accounts
Regulatory Liabilities
Regulatory Liabilities, Current	580	484
Regulatory Liabilities, Long-term	1,210	1,091
Southern California Edison | Costs of Removal
Regulatory Liabilities
Regulatory Liabilities, Long-term	2,814	2,731
Southern California Edison | Asset Retirement Obligations
Regulatory Liabilities
Regulatory Liabilities, Long-term	$954	$1,385

Regulatory_Assets_and_Liabilit3

Regulatory Assets and Liabilities (Textual) (Details) (San Onofre (nuclear), Southern California Edison, USD $)	1 Months Ended	9 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2013	Sep. 30, 2013
Regulatory Assets [Line Items]
Net regulatory asset		$1,450
Cost of service	56	-129
Property, plant and equipment
Regulatory Assets [Line Items]
Net regulatory asset		1,540
Estimated losses on disposal of nuclear fuel inventory
Regulatory Assets [Line Items]
Net regulatory asset		$33

Commitments_and_Contingencies_

Commitments and Contingencies (Operating Leases) (Details) (Southern California Edison, USD $)	Sep. 30, 2013
Southern California Edison
Lease Disclosures [Line Items]
Future minimum payments due, 2014	$247,000,000
Future minimum payments due, 2015	340,000,000
Future minimum payments due, 2016	413,000,000
Future minimum payments due, 2017	415,000,000
Future minimum payments due, 2018	$4,430,000,000

Commitments_and_Contingencies_1

Commitments and Contingencies (Details) (USD $)

1 Months Ended

1 Months Ended

9 Months Ended

9 Months Ended

12 Months Ended

1 Months Ended

9 Months Ended

9 Months Ended

Jun. 30, 2010

Sep. 30, 2013

Dec. 31, 2011

Sep. 30, 2013

Sep. 01, 2013

Jun. 01, 2013

Sep. 30, 2013

Sep. 30, 2013

Dec. 31, 2007

31-May-13

Oct. 31, 2011

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Jun. 30, 2013

Sep. 30, 2013

Jun. 30, 2013

Sep. 30, 2013

31-May-13

31-May-13

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2013

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

Edison International

Malibu Fire Order Instituting Investigation

Malibu Fire Order Instituting Investigation

Alleged violations of PSD requirements and New Source Performance Standards of the CAA

Nuclear Insurance

Nuclear Insurance

Nuclear Insurance

San Onofre (nuclear)

San Onofre (nuclear)

San Onofre (nuclear)

San Onofre and Palo Verde

Pole Safety Studies and Remediation

Penalty Paid to State General Fund

Nuclear fuel supply commitments

Nuclear fuel supply commitments

Dividends Paid By EME to Holdings [Member]

Amount Paid By EME Under Tax Allocation Scheme [Member]

sites

Environmental Indemnities

sites

Southern California Edison

Southern California Edison

Southern California Edison

Southern California Edison

SCE and other owners of San Onofre and Palo Verde

Southern California Edison

Southern California Edison

Nuclear Insurance

Malibu Fire Order Instituting Investigation

Malibu Fire Order Instituting Investigation

Southern California Edison

Southern California Edison

Eme Chapter 11 Bankruptcy Filing [Member]

Eme Chapter 11 Bankruptcy Filing [Member]

power_pole

private_environmental_organization

Southern California Edison

Southern California Edison

Southern California Edison

Schedule Of Commitments And Contingencies [Line Items]

Supply commitment

$912,000,000

Accrued liabilities related to cancellation of contracts

33,000,000

Maximum liability for purchase agreement for damages

60,000,000

Notice Of Claim Amount

390,000,000

306,000,000

925,000,000

183,000,000

Number of failed power poles (in power poles)

3

Proposed settlement amount

37,000,000

17,000,000

20,000,000

Number of plaintiffs (entities)

4

Identified material sites for environmental remediation (in number of sites)

19

Minimum costs to be Identified Site

1,000,000

Minimum liability for environmental remediation for material sites

129,000,000

90,000,000

Immaterial sites for environmental remediation (in number of sites)

39

Immaterial sites, range of liability, minimum

4,000,000

Environmental remediation liability

133,000,000

Regulatory assets related to environmental remediation

129,000,000

Portion of recorded liability recoverable from incentive mechanism

38,000,000

Percentage of environmental remediation costs recoverable through an incentive mechanism (as a percent)

90.00%

Liability incurred at majority of the remaining sites through customer rates

91,000,000

Environmental remediation costs to be recovered (as a percent)

100.00%

Amount that cleanup costs could exceed recorded liability for identified material sites

161,000,000

Amount that cleanup costs could exceed recorded liability for immaterial sites

7,000,000

Maximum expected period for cleanup of identified sites (in years)

30 years

Expected annual environmental remediation costs, low end of range

6,000,000

Expected annual environmental remediation costs, high end of range

31,000,000

Environmental remediation costs

5,000,000

Federal limit on public liability claims from nuclear incident, approximate

13,600,000,000

Private primary insurance purchased

375,000,000

Maximum assessment per each nuclear incident

255,000,000

Maximum yearly assessment per nuclear incident

38,000,000

Loss limit, property damage insurance

500,000,000

Loss limit, property damage insurance, federal minimum requirement

1,060,000,000

Limit on assessment of retrospective premium adjustments, per year, approximate

52,000,000

Insurance coverage for wildfire liabilities Limit

500,000,000

450,000,000

Self insurance retention per wildfire occurrence

10,000,000

Wildfire Threshold For Additional Coverage

550,000,000

Amount of damages, decision by US Court of Federal Claims, spent nuclear fuel litigation

142,000,000

Damages sought

$98,000,000

Preferred_and_Preference_Stock1

Preferred and Preference Stock of Utility (Details) (SCE Trust II, Southern California Edison, Series G Preferred Stock, USD $)	3 Months Ended
	Mar. 31, 2013	Jan. 31, 2013
SCE Trust II | Southern California Edison | Series G Preferred Stock
Preferred and Preference Stock of Utility
Shares issued (in shares)	160,004
Preference stock dividend rate (percent)	5.10%
Liquidation value (in dollars per share)	$2,500	$2,500

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Loss (Details) (USD $)	3 Months Ended			9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013		Sep. 30, 2012	Sep. 30, 2013		Sep. 30, 2012
Increase (Decrease) in Accumulated Other Comprehensive Loss
Balance at the beginning of period				($87)
Net current-period other comprehensive loss	3		-11	8		-29
Balance at the end of period	-79			-79
Reclassification Adjustment out of Accumulated Other Comprehensive Loss [Abstract]
Tax expense	177		228	173		421
Total reclassification, net of tax	463		215	689		423
Southern California Edison
Increase (Decrease) in Accumulated Other Comprehensive Loss
Balance at the beginning of period				-29
Net current-period other comprehensive loss	2		1	1		1
Balance at the end of period	-28			-28
Reclassification Adjustment out of Accumulated Other Comprehensive Loss [Abstract]
Tax expense	183		176	196		384
Total reclassification, net of tax	502		388	717		802
Accumulated Defined Benefit Plans Adjustment
Increase (Decrease) in Accumulated Other Comprehensive Loss
Balance at the beginning of period	-82			-87
Other comprehensive loss before reclassifications	0			-2
Amounts reclassified from accumulated other comprehensive loss	3	[1]		10	[1]
Net current-period other comprehensive loss	3			8
Balance at the end of period	-79			-79
Accumulated Defined Benefit Plans Adjustment | Southern California Edison
Increase (Decrease) in Accumulated Other Comprehensive Loss
Balance at the beginning of period	-30			-29
Other comprehensive loss before reclassifications	0			-4
Amounts reclassified from accumulated other comprehensive loss	2	[1]		5	[1]
Net current-period other comprehensive loss	2			1
Balance at the end of period	-28			-28
Accumulated Defined Benefit Plans Adjustment | Reclassification out of Accumulated Other Comprehensive Loss
Reclassification Adjustment out of Accumulated Other Comprehensive Loss [Abstract]
Amortization of net loss included in net income	4			13
Tax expense	1			3
Total reclassification, net of tax	3			10
Accumulated Defined Benefit Plans Adjustment | Reclassification out of Accumulated Other Comprehensive Loss | Southern California Edison
Reclassification Adjustment out of Accumulated Other Comprehensive Loss [Abstract]
Amortization of net loss included in net income	3			8
Tax expense	1			3
Total reclassification, net of tax	$2			$5
[1]	These items are included in the computation of net periodic pension and PBOP expense. See Note 8 for additional information.

Interest_and_Other_Income_and_2

Interest and Other Income and Expenses (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Other income:
Total consolidated interest and other income	$28	$38	$91	$110
Other expenses:
Total consolidated other expenses	15	10	38	36
Southern California Edison
Other income:
Equity allowance for funds used during construction	14	23	54	71
Increase in cash surrender value of life insurance policies	10	6	24	20
Interest income	2	2	8	5
Other	1	7	3	12
Total interest and other income	27	38	89	108
Total consolidated interest and other income	27	38	89	108
Other expenses:
Civic, political and related activities and donations	9	5	24	22
Other	6	4	14	14
Total other expenses	15	9	38	36
Total consolidated other expenses	15	9	38	36
Edison International
Other income:
Other income	1	0	2	2
Other expenses:
Other expenses	$0	$1	$0	$0

Discontinued_Operations_Detail

Discontinued Operations (Details) (USD $)	3 Months Ended	9 Months Ended			3 Months Ended	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013
					Edison Mission Energy	Edison Mission Energy	Edison Mission Energy	Plan Support Agreement
							Pension Plans
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income tax expense from discontinued operations		$25			$25	$1
Operating revenues from discontinued operations	461		1,310
Loss from discontinued operation before income taxes	262		645
Pensions and benefits		2,237		2,614			80
Joint tax liability					192	192
Receivables from EME					238	238
Deconsolidated charges recorded in accumulated other comprehensive income							34
Net receivable under plan support agreement								46
Retirement liabilities assumed under plan support agreement								104
Estimated loss under plan support agreement								$150

Supplemental_Cash_Flows_Inform2

Supplemental Cash Flows Information (Details) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Cash payments (receipts) for interest and taxes:
Interest, net of amounts capitalized	$431	$394
Tax payments (refunds), net	27	-239
Dividends declared but not paid:
Common stock	110	106
Preferred and preference stock	4	6
Southern California Edison
Cash payments (receipts) for interest and taxes:
Interest, net of amounts capitalized	415	394
Tax payments (refunds), net	18	-243
Dividends declared but not paid:
Common stock	120	0
Preferred and preference stock	4	6
Accrued capital expenditures	$401	$414