Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2018	Oct. 26, 2018
Entity Information [Line Items]
Entity Registrant Name	EDISON INTERNATIONAL
Entity Central Index Key	0000827052
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Common Stock, Shares Outstanding		325,811,206
Southern California Edison
Entity Information [Line Items]
Entity Registrant Name	SOUTHERN CALIFORNIA EDISON CO
Entity Central Index Key	0000092103
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Common Stock, Shares Outstanding		434,888,104

Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Total operating revenue	$ 4,269	$ 3,672	$ 9,648	$ 9,100
Purchased power and fuel	2,306	1,783	4,344	3,742
Operation and maintenance	674	721	2,068	2,031
Depreciation and amortization	466	524	1,391	1,535
Property and other taxes	97	98	301	284
Impairment and other	(11)	0	60	22
Other operating income	(2)	(7)	(5)	(8)
Total operating expenses	3,530	3,119	8,159	7,606
Operating income	739	553	1,489	1,494
Interest expense	(188)	(162)	(538)	(473)
Other income and expense	76	41	176	98
Income from continuing operations before income taxes	627	432	1,127	1,119
Income tax expense (benefit)	83	(69)	43	(83)
Income from continuing operations	544	501	1,084	1,202
Net income	544	501	1,084	1,202
Preferred and preference stock dividend requirements of SCE	31	32	91	94
Other noncontrolling interests	0	(1)	(14)	(2)
Net income available for common stock	513	470	1,007	1,110
Amounts attributable to Edison International common shareholders:
Income from continuing operations, net of tax	513	470	1,007	1,110
Net income available for common stock	$ 513	$ 470	$ 1,007	$ 1,110
Basic earnings per share:
Weighted average common shares outstanding (in shares)	326	326	326	326
Basic earnings per common share attributable to Edison International common shareholders (in dollars per share)	$ 1.57	$ 1.44	$ 3.09	$ 3.41
Diluted earnings per share:
Weighted-average shares of common stock outstanding, including effect of dilutive securities (in shares)	327	328	327	329
Diluted earnings per common share attributable to Edison International common shareholders (in dollars per share)	$ 1.57	$ 1.43	$ 3.08	$ 3.38
Dividends declared per common share (in dollars per share)	$ 0.6050	$ 0.5425	$ 1.815	$ 1.6275
Southern California Edison Company
Total operating revenue	$ 4,260	$ 3,652	$ 9,617	$ 9,061
Purchased power and fuel	2,306	1,783	4,344	3,742
Operation and maintenance	651	690	1,996	1,945
Depreciation and amortization	466	521	1,387	1,528
Property and other taxes	96	97	298	279
Impairment and other	(10)	0	(10)	0
Other operating income	(3)	(8)	(5)	(8)
Total operating expenses	3,506	3,083	8,010	7,486
Operating income	754	569	1,607	1,575
Interest expense	(173)	(149)	(492)	(436)
Other income and expense	72	42	173	110
Income from continuing operations before income taxes	653	462	1,288	1,249
Income tax expense (benefit)	86	(35)	78	34
Net income	567	497	1,210	1,215
Preferred and preference stock dividend requirements of SCE	31	32	91	94
Net income available for common stock	536	465	1,119	1,121
Amounts attributable to Edison International common shareholders:
Net income available for common stock	$ 536	$ 465	$ 1,119	$ 1,121

Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Net income	$ 544	$ 501	$ 1,084	$ 1,202
Pension and postretirement benefits other than pensions:
Amortization of net loss included in net income	1	2	5	5
Other	1	(2)	(4)	0
Other comprehensive income, net of tax	2	0	1	5
Comprehensive income	546	501	1,085	1,207
Less: Comprehensive income attributable to noncontrolling interests	31	31	77	92
Comprehensive income attributable to Edison International	515	470	1,008	1,115
Southern California Edison Company
Net income	567	497	1,210	1,215
Pension and postretirement benefits other than pensions:
Amortization of net loss included in net income	1	0	4	2
Other	0	0	(5)	0
Other comprehensive income, net of tax	1	0	(1)	2
Comprehensive income	$ 568	$ 497	$ 1,209	$ 1,217

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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+ Details

Consolidated Balance Sheets - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
ASSETS
Cash and cash equivalents	$ 71	$ 1,091
Receivables, less allowances	1,044	717
Accrued unbilled revenue	505	212
Inventory	261	242
Income tax receivables	167	224
Prepaid expenses	188	233
Derivative assets	77	105
Regulatory assets	913	703
Other current assets	157	202
Total current assets	3,383	3,729
Nuclear decommissioning trusts	4,330	4,440
Other investments	59	73
Total investments	4,389	4,513
Utility property, plant and equipment, less accumulated depreciation and amortization of $9,533 and $9,355 at respective dates	40,333	38,708
Nonutility property, plant and equipment, less accumulated depreciation	79	342
Total property, plant and equipment	40,412	39,050
Regulatory assets	5,046	4,914
Other long-term assets	333	374
Total long-term assets	5,379	5,288
Total assets	53,563	52,580
LIABILITIES AND EQUITY
Short-term debt	103	2,393
Current portion of long-term debt	79	481
Accounts payable	1,288	1,503
Accrued taxes	102	23
Customer deposits	297	281
Regulatory liabilities	1,599	1,121
Other current liabilities	1,251	1,266
Total current liabilities	4,719	7,068
Long-term debt	14,629	11,642
Deferred income taxes and credits	5,043	4,567
Pensions and benefits	897	943
Asset retirement obligations	2,890	2,908
Regulatory liabilities	8,463	8,614
Other deferred credits and other long-term liabilities	2,633	2,953
Total deferred credits and other liabilities	19,926	19,985
Total liabilities	39,274	38,695
Commitments and contingencies (Note 12)
Redeemable noncontrolling interest	0	19
Common stock, no par value	2,541	2,526
Accumulated other comprehensive loss	(42)	(43)
Retained earnings	9,597	9,188
Total common shareholder's equity	12,096	11,671
Noncontrolling interests – preferred and preference stock of SCE	2,193	2,193
Other noncontrolling interests	0	2
Total equity	14,289	13,866
Total liabilities and equity	53,563	52,580
Southern California Edison Company
ASSETS
Cash and cash equivalents	39	515
Receivables, less allowances	1,032	693
Accrued unbilled revenue	505	212
Inventory	261	242
Income tax receivables	230	229
Prepaid expenses	181	228
Derivative assets	77	105
Regulatory assets	913	703
Other current assets	154	160
Total current assets	3,392	3,087
Nuclear decommissioning trusts	4,330	4,440
Other investments	39	52
Total investments	4,369	4,492
Utility property, plant and equipment, less accumulated depreciation and amortization of $9,533 and $9,355 at respective dates	40,333	38,708
Nonutility property, plant and equipment, less accumulated depreciation	74	77
Total property, plant and equipment	40,407	38,785
Regulatory assets	5,046	4,914
Other long-term assets	216	237
Total long-term assets	5,262	5,151
Total assets	53,430	51,515
LIABILITIES AND EQUITY
Short-term debt	103	1,238
Current portion of long-term debt	79	479
Accounts payable	1,290	1,519
Accrued taxes	105	24
Customer deposits	297	281
Regulatory liabilities	1,599	1,121
Other current liabilities	1,329	1,225
Total current liabilities	4,802	5,887
Long-term debt	12,890	10,428
Deferred income taxes and credits	6,367	5,890
Pensions and benefits	446	483
Asset retirement obligations	2,890	2,892
Regulatory liabilities	8,463	8,614
Other deferred credits and other long-term liabilities	2,355	2,649
Total deferred credits and other liabilities	20,521	20,528
Total liabilities	38,213	36,843
Commitments and contingencies (Note 12)
Common stock, no par value	2,168	2,168
Additional paid-in capital	678	671
Accumulated other comprehensive loss	(20)	(19)
Retained earnings	10,146	9,607
Total common shareholder's equity	12,972	12,427
Noncontrolling interests – preferred and preference stock of SCE	2,245	2,245
Total equity	15,217	14,672
Total liabilities and equity	$ 53,430	$ 51,515

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Receivables, allowances for uncollectible accounts	$ 56	$ 54
Utility property, plant and equipment, accumulated depreciation	9,533	9,355
Nonutility property, plant and equipment, accumulated depreciation	$ 80	$ 114
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 Company
Receivables, allowances for uncollectible accounts	$ 56	$ 53
Utility property, plant and equipment, accumulated depreciation	9,533	9,355
Nonutility property, plant and equipment, accumulated depreciation	$ 76	$ 97
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 Cash Flows - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities:
Net income	$ 1,084	$ 1,202
Adjustments to reconcile to net cash provided by operating activities:
Depreciation and amortization	1,639	1,591
Allowance for equity during construction	(76)	(65)
Impairment and other	60	22
Deferred income taxes and investment tax credits	133	77
Other	48	17
Nuclear decommissioning trusts	(86)	(117)
Changes in operating assets and liabilities:
Receivables	(325)	(387)
Inventory	(25)	10
Accounts payable	20	(11)
Tax receivables and payables	137	(128)
Other current assets and liabilities	(424)	(40)
Regulatory assets and liabilities, net	213	560
Other noncurrent assets and liabilities	(127)	(33)
Net cash provided by operating activities	2,271	2,698
Cash flows from financing activities:
Long-term debt issued or remarketed, net of discount and issuance costs	3,237	2,236
Long-term debt matured	(654)	(1,182)
Preference stock issued, net	0	463
Preference stock redeemed	0	(475)
Short-term debt financing, net	(2,228)	(401)
Payments for stock-based compensation	(37)	(365)
Receipts from stock option exercises	20	201
Dividends and distributions to noncontrolling interests	(96)	(100)
Dividends paid	(591)	(530)
Other	38	(23)
Net cash used in financing activities	(311)	(176)
Cash flows from investing activities:
Capital expenditures	(3,241)	(2,674)
Proceeds from sale of nuclear decommissioning trust investments	3,017	3,974
Purchases of nuclear decommissioning trust investments	(2,931)	(3,857)
Proceeds from sale of SoCore Energy, net of cash acquired by buyer	78	0
Other	64	54
Net cash used in investing activities	(3,013)	(2,503)
Net (decrease) increase in cash, cash equivalents and restricted cash	(1,053)	19
Cash, cash equivalents and restricted cash at beginning of period	1,132	114
Cash, cash equivalents and restricted cash at end of period	79	133
Southern California Edison Company
Cash flows from operating activities:
Net income	1,210	1,215
Adjustments to reconcile to net cash provided by operating activities:
Depreciation and amortization	1,632	1,581
Allowance for equity during construction	(76)	(65)
Impairment and other	(10)	0
Deferred income taxes and investment tax credits	108	337
Other	43	9
Nuclear decommissioning trusts	(86)	(117)
Changes in operating assets and liabilities:
Receivables	(337)	(389)
Inventory	(25)	11
Accounts payable	2	(16)
Tax receivables and payables	80	(146)
Other current assets and liabilities	(412)	(36)
Regulatory assets and liabilities, net	213	560
Other noncurrent assets and liabilities	(84)	(143)
Net cash provided by operating activities	2,258	2,801
Cash flows from financing activities:
Long-term debt issued or remarketed, net of discount and issuance costs	2,692	1,445
Long-term debt matured	(639)	(781)
Preference stock issued, net	0	463
Preference stock redeemed	0	(475)
Short-term debt financing, net	(1,137)	(441)
Payments for stock-based compensation	(16)	(80)
Receipts from stock option exercises	8	45
Dividends paid	(570)	(481)
Other	2	(34)
Net cash used in financing activities	340	(339)
Cash flows from investing activities:
Capital expenditures	(3,223)	(2,610)
Proceeds from sale of nuclear decommissioning trust investments	3,017	3,974
Purchases of nuclear decommissioning trust investments	(2,931)	(3,857)
Other	63	52
Net cash used in investing activities	(3,074)	(2,441)
Net (decrease) increase in cash, cash equivalents and restricted cash	(476)	21
Cash, cash equivalents and restricted cash at beginning of period	515	40
Cash, cash equivalents and restricted cash at end of period	$ 39	$ 61

Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2018

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Organization and Basis of Presentation

Edison International is the parent holding company of Southern California Edison Company ("SCE") and Edison Energy Group, Inc. ("Edison Energy Group"). SCE is an investor-owned public utility primarily engaged in the business of supplying and delivering electricity to an approximately 50,000 square mile area of southern California. Edison Energy Group is a holding company for subsidiaries engaged in operating competitive businesses, primarily consisting of Edison Energy, LLC ("Edison Energy") which provides energy services to commercial and industrial customers. Edison Energy's 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 competitive subsidiaries and "Edison International Parent" refer to Edison International on a stand-alone basis, not consolidated with its 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 Edison International's and SCE's combined Annual Report on Form 10-K for the year ended December 31, 2017 (the "2017 Form 10-K"). This quarterly report should be read in conjunction with the financial statements and notes included in the 2017 Form 10-K.

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 ("GAAP") for the periods covered by this quarterly report on Form 10-Q. The results of operations for the three- and nine- month period ended September 30, 2018 are not necessarily indicative of the operating results for the full year.

The December 31, 2017 financial statement data was derived from audited financial statements, but does not include all disclosures required by GAAP.

Effective January 1, 2018, Edison International and SCE adopted several accounting standards retrospectively. Prior year financial statements have been reclassified and updated to reflect the retrospective application of these standards as applicable. For further information, see "New Accounting Guidance" below.

Sale of SoCore Energy

On February 28, 2018, Edison International agreed to sell SoCore Energy LLC ("SoCore Energy"), a subsidiary of Edison Energy Group, to a third party, subject to the completion of closing conditions, which were satisfied on April 16, 2018. As a result, Edison International recognized a pre-tax loss of $62 million ($50 million after-tax) for the nine months ended September 30, 2018 and, beginning in the second quarter of 2018, the assets and liabilities of SoCore Energy were not reflected in the consolidated Edison International balance sheet.

Cash, Cash Equivalents and Restricted Cash

Cash equivalents include 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, 2018		December 31, 2017		September 30, 2018		December 31, 2017
Money market funds	$	30	$	1,024	$	6	$	483

Cash is temporarily invested until required for check clearing. 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, 2018		December 31, 2017		September 30, 2018		December 31, 2017
Book balances reclassified to accounts payable	$	73	$	64	$	73	$	63

Edison International's restricted cash at September 30, 2018 and December 31, 2017 was $8 million and $41 million, respectively. Restricted cash at December 31, 2017 primarily relates to funds held by SoCore Energy and its consolidated affiliates pursuant to project financing or purchase agreements, most of which lapsed before June 30, 2018. As a result of the sale of SoCore Energy, beginning in the second quarter of 2018, the assets and liabilities of SoCore Energy were not included in the consolidated Edison International balance sheet as discussed above.

The following table sets forth the cash, cash equivalents and restricted cash included in the consolidated statements of cash flows:



(in millions)	September 30, 2018		December 31, 2017
Edison International:
Cash and cash equivalents	$	71	$	1,091
Short-term restricted cash ¹	1		40
Long-term restricted cash ²	7		1
Total cash, cash equivalents, and restricted cash	$	79	$	1,132
SCE:
Cash and cash equivalents	$	39	$	515
Total cash, cash equivalents, and restricted cash	$	39	$	515


¹	Reflected in "Other current assets" on Edison International's consolidated balance sheets.


²	Reflected in "Other long-term assets" on Edison International's consolidated balance sheets.

Goodwill

At September 30, 2018, Edison International has $78 million of goodwill, all of which is related to its Edison Energy reporting unit. Goodwill constitutes the majority of Edison International's $104 million investment in Edison Energy. Edison International assesses goodwill through an annual goodwill impairment test, at the reporting unit level as of October 1st of each year. Edison International will update its goodwill impairment test between annual tests if events occur or circumstances change such that it is more likely than not that the fair value of a reporting unit is below its carrying value. The fair value of the Edison Energy reporting unit is estimated using the income approach, which utilizes discounted cash flow analysis based on the earnings expected to be generated in the future. This determination requires significant assumptions and estimates in forecasting future cash flows and establishing a market discount rate and a terminal value. The most critical assumption affecting the estimate of the Edison Energy reporting unit's fair value is its forecasted growth in sales to commercial and industrial customers. Edison Energy is currently in the process of updating its long-term plan. A reduction in expected future cash flows could result in a goodwill impairment.

Revenue Recognition

During the first nine months of 2018, pending the outcome of the 2018 GRC decision, SCE recognized GRC-related revenue based on the 2017 authorized revenue requirement, adjusted for the July 2017 cost of capital decision and the impact of Tax Reform. The amounts billed to customers for the first nine months of 2018 were based on the 2017 authorized revenue requirement and a regulatory liability has been established to record the associated adjustments. See Note 11 for further details. The CPUC has authorized the establishment of a GRC memorandum account, which will make the 2018 revenue requirement ultimately adopted by the CPUC effective as of January 1, 2018. SCE cannot predict the revenue requirement the CPUC will authorize or provide assurance on the timing of a final decision.

In October 2017, SCE filed its new formula rate with the FERC. In December 2017, the FERC issued an order setting the effective date of SCE's new FERC formula rate as of January 1, 2018, subject to settlement procedures and refund. Pending resolution of the FERC formula rate proceeding, SCE is recognizing revenue based on the FERC formula rate adjusted for the impact of Tax Reform and other adjustments.

Earnings Per Share

Edison International computes earnings per common 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 restricted stock units, which earn dividend equivalents on an equal basis with common shares once the awards are vested. EPS attributable to Edison International common shareholders was computed as follows:



	Three months ended September 30,				Nine months ended September 30,
(in millions, except per-share amounts)	2018		2017		2018		2017
Basic earnings per share – continuing operations:
Income from continuing operations attributable to common shareholders	$	513	$	470	$	1,007	$	1,110
Participating securities dividends	—		—		—		—
Income from continuing operations available to common shareholders	$	513	$	470	$	1,007	$	1,110
Weighted average common shares outstanding	326		326		326		326
Basic earnings per share – continuing operations	$	1.57	$	1.44	$	3.09	$	3.41
Diluted earnings per share – continuing operations:
Income from continuing operations attributable to common shareholders	$	513	$	470	$	1,007	$	1,110
Participating securities dividends	—		—		—		—
Income from continuing operations available to common shareholders	$	513	$	470	$	1,007	$	1,110
Income impact of assumed conversions	—		—		—		—
Income from continuing operations available to common shareholders and assumed conversions	$	513	$	470	$	1,007	$	1,110
Weighted average common shares outstanding	326		326		326		326
Incremental shares from assumed conversions	1		2		1		3
Adjusted weighted average shares – diluted	327		328		327		329
Diluted earnings per share – continuing operations	$	1.57	$	1.43	$	3.08	$	3.38

In addition to the participating securities discussed above, Edison International also may award stock options, which are payable in common shares and are included in the diluted earnings per share calculation. Stock option awards to purchase 3,817,072 and 1,365,671 shares of common stock for the three months ended September 30, 2018 and 2017, respectively, and 6,042,695 and 1,373,736 shares for the nine months ended September 30, 2018 and 2017, respectively, were outstanding, but were not included in the computation of diluted earnings per share because the effect would have been antidilutive.

New Accounting Guidance

Accounting Guidance Adopted

In May 2014, the Financial Accounting Standards Board ("FASB") issued an accounting standards update on revenue recognition and further amended the standard in 2016 and 2017. Under the new standard, revenue is recognized when a good or service is transferred to the customer and the customer obtains control of the good or service. Some revenue arrangements, such as alternative revenue programs which include balancing account overcollections and undercollections, are excluded from the scope of the new standard and, therefore, will be accounted for and presented separately from revenue recognized from contracts with customers in the disclosures. Edison International and SCE adopted this standard effective January 1, 2018, using the modified retrospective method for contracts that were not completed as of the adoption date. Edison International recognized a cumulative effect adjustment to increase the opening balance of retained earnings by approximately $5 million ($7 million pre-tax) on January 1, 2018. This adjustment is related to variable consideration recognized at Edison Energy which is not subject to potential significant reversal and has no further performance obligations. See Note 7 for further details.

In January 2016, the FASB issued an accounting standards update that amends the guidance on the classification and measurement of financial instruments, and further amended the guidance in 2018. Under the new guidance, equity investments (excluding those accounted for under the equity method or those that result in consolidation) are required to be measured at fair value, with changes in fair value recognized in net income. The new guidance also amends certain disclosure requirements associated with the fair value of financial instruments and requires financial assets and financial liabilities to be presented separately in the notes to the financial statements, grouped by measurement category and form of financial assets. Edison International and SCE adopted this guidance effective January 1, 2018. Edison International and SCE recognized a cumulative effect adjustment to increase the opening balance of retained earnings and accumulated other comprehensive loss by $5 million ($8 million pre-tax) on January 1, 2018. See Note 2 for further details.

In August and November 2016, the FASB issued two accounting standards updates to clarify the presentation and classification of certain cash receipts and payments in the statement of cash flows and to require restricted cash to be presented with cash and cash equivalents in the statement of cash flows. Edison International and SCE adopted these standards effective January 1, 2018, using the retrospective approach. The adoption of these standards did not have a material impact on Edison International's and SCE's consolidated statement of cash flows.

In March 2017, the FASB issued an accounting standards update on the presentation of the components of net periodic benefit cost for an entity's defined benefit pension and other postretirement plans. Edison International and SCE adopted this guidance retrospectively with respect to the income statement presentation requirement and prospectively for the capitalization requirement, effective January 1, 2018. The adoption of this standard did not have a material impact on Edison International's and SCE's consolidated financial statements, but did result in the separate presentation of service costs as an operating expense and non-service costs within other income and expenses and the limitation of the capitalization of benefit costs to the service cost component. During the three and nine months ended September 30, 2017, non-service benefits totaled $8 million and $15 million, respectively, for Edison International and $9 million and $27 million, respectively, for SCE, which were reclassified from "Operation and maintenance" to "Other income and expenses." See Note 9 and Note 14 for further details.

Accounting Guidance Not Yet Adopted

In February 2016, the FASB issued an accounting standards update related to lease accounting and further amended the standard in 2018. The new guidance is effective January 1, 2019. Under the new standard, a lease is defined as a contract, or part of a contract, that conveys the right to control the use of identified assets for a period of time in exchange for consideration. Lessees are required to recognize leases on the balance sheet as a right-of-use asset and a related lease liability, and classify the leases as either operating or finance. The liability will be equal to the present value of the lease payments. The asset will be based on the liability, subject to adjustments, such as lease incentives. Edison International's operating leases will result in straight-line expense while finance leases will result in a higher initial expense pattern due to the interest component. SCE, as a regulated entity, is permitted to continue to recognize expense using the timing that conforms to the regulatory rate treatment. In accordance with the new guidance, Edison International and SCE will elect the package of practical expedients not to reassess prior conclusions related to contracts containing leases, lease classification, and initial direct costs and the practical expedient not to assess whether existing land easements are or contain a lease. Edison International and SCE will adopt this guidance effective January 1, 2019, using the modified retrospective approach, for leases that existed as of the adoption date and will elect the optional transition method not to restate periods prior to the adoption date. The adoption of this standard will increase right-of-use assets and lease liabilities in Edison International's and SCE's consolidated balance sheets. Edison International and SCE have implemented a new lease accounting system and are in the process of finalizing the quantitative impact this standard will have on the consolidated balance sheets and the lease disclosures.

The FASB issued an accounting standards update related to the impairment of financial instruments, effective January 1, 2020. The new guidance provides an impairment model, known as the current expected credit loss model, which is based on expected credit losses rather than incurred losses. Edison International and SCE are currently evaluating the impact of this new guidance.

In January 2017, the FASB issued an accounting standards update to simplify the accounting for goodwill impairment by changing the procedural steps to apply the goodwill impairment test. After the adoption of this accounting standards update, goodwill impairment will be measured as the amount by which a reporting unit's carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. Edison International will apply this guidance to goodwill impairment tests beginning in 2020.

In February 2018, the FASB issued an accounting standards update to provide entities an election to reclassify stranded tax effects resulting from Tax Reform from accumulated other comprehensive income to retained earnings. Stranded tax effects originated in December 2017 when deferred taxes were re-measured at the lower federal corporate tax rate with the impact included in operating income but the tax effects of items within accumulated other comprehensive income were not similarly adjusted. Edison International and SCE will adopt this guidance on January 1, 2019 and reclassify stranded tax effects of $10 million and $5 million, respectively, from accumulated other comprehensive income to retained earnings in the period of adoption.

In August 2018, the FASB issued an accounting standards update which aligns the requirement for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing costs incurred to develop or obtain internal-use software. The guidance also clarified presentation requirements for reporting implementation costs in the financial statements. The guidance is effective January 1, 2020 with early adoption permitted. Edison International and SCE are currently evaluating the impact of the guidance.

In August 2018, the FASB issued two accounting standards updates to remove, modify, and add certain disclosure requirements related to fair value measurement and employer-sponsored defined benefit pension or other postretirement plans. The guidance is effective January 1, 2020 and 2021, respectively, with early adoption permitted. Edison International and SCE are currently evaluating the impact of the guidance.

Consolidated Statements of Changes in Equity

9 Months Ended

Sep. 30, 2018

Equity [Abstract]

Consolidated Statements of Changes in Equity

The following table provides Edison International's changes in equity for the nine months ended September 30, 2018:



	Equity Attributable to Common Shareholders											Noncontrolling Interests
(in millions, except per-share amounts)	Common Stock		Accumulated Other Comprehensive Loss			Retained Earnings			Subtotal			Other			Preferred and Preference Stock			Total Equity
Balance at December 31, 2017	$	2,526	$	(43	)	$	9,188		$	11,671		$	2		$	2,193		$	13,866
Net income	—		—			1,007			1,007			(11		)	91			1,087
Other comprehensive income	—		6			—			6			—			—			6
Cumulative effect of accounting changes¹	—		(5		)	10			5			—			—			5
Contributions from tax equity investor	—		—			—			—			24			—			24
Common stock dividends declared ($1.8150 per share)	—		—			(591		)	(591		)	—			—			(591		)
Dividends to noncontrolling interests	—		—			—			—			—			(91		)	(91		)
Stock-based compensation	—		—			(17		)	(17		)	—			—			(17		)
Noncash stock-based compensation	15		—			—			15			—			—			15
Deconsolidation of SoCore Energy	—		—			—			—			(15		)	—			(15		)
Balance at September 30, 2018	$	2,541	$	(42	)	$	9,597		$	12,096		$	—		$	2,193		$	14,289


¹	Edison International recognized cumulative effect adjustments to the opening balance of retained earnings and accumulated other comprehensive loss on January 1, 2018 related to the adoption of the accounting standards updates on revenue recognition and measurement of financial instruments.

The following table provides Edison International's changes in equity for the nine months ended September 30, 2017:



	Equity Attributable to Common Shareholders											Noncontrolling Interests
(in millions, except per-share amounts)	Common Stock		Accumulated Other Comprehensive Loss			Retained Earnings			Subtotal			Preferred and Preference Stock			Total Equity
Balance at December 31, 2016	$	2,505	$	(53	)	$	9,544		$	11,996		$	2,191		$	14,187
Net income	—		—			1,110			1,110			94			1,204
Other comprehensive income	—		5			—			5			—			5
Common stock dividends declared ($1.6275 per share)	—		—			(530		)	(530		)	—			(530		)
Dividends to noncontrolling interests	—		—			—			—			(94		)	(94		)
Stock-based compensation	—		—			(165		)	(165		)	—			(165		)
Noncash stock-based compensation	15		—			—			15			—			15
Issuance of preference stock	—		—			—			—			463			463
Redemption of preference stock	—		—			(15		)	(15		)	(460		)	(475		)
Balance at September 30, 2017	$	2,520	$	(48	)	$	9,944		$	12,416		$	2,194		$	14,610

The following table provides SCE's changes in equity for the nine months ended September 30, 2018:



	Equity Attributable to Edison International
(in millions)	Common Stock		Additional Paid-in Capital		Accumulated Other Comprehensive Loss			Retained Earnings			Preferred and Preference Stock		Total Equity
Balance at December 31, 2017	$	2,168	$	671	$	(19	)	$	9,607		$	2,245	$	14,672
Net income	—		—		—			1,210			—		1,210
Other comprehensive income	—		—		4			—			—		4
Cumulative effect of accounting change¹	—		—		(5		)	5			—		—
Dividends declared on common stock	—		—		—			(576		)	—		(576		)
Dividends declared on preferred and preference stock	—		—		—			(91		)	—		(91		)
Stock-based compensation	—		—		—			(9		)	—		(9		)
Noncash stock-based compensation	—		7		—			—			—		7
Balance at September 30, 2018	$	2,168	$	678	$	(20	)	$	10,146		$	2,245	$	15,217


¹	SCE recognized a cumulative effect adjustment to the opening balance of retained earnings and accumulated other comprehensive loss on January 1, 2018 related to the adoption of the accounting standards update on measurement of financial instruments.

The following table provides SCE's changes in equity for the nine months ended September 30, 2017:



	Equity Attributable to Edison International
(in millions)	Common Stock		Additional Paid-in Capital			Accumulated Other Comprehensive Loss			Retained Earnings			Preferred and Preference Stock			Total Equity
Balance at December 31, 2016	$	2,168	$	657		$	(20	)	$	9,433		$	2,245		$	14,483
Net income	—		—			—			1,215			—			1,215
Other comprehensive income	—		—			2			—			—			2
Dividends declared on common stock	—		—			—			(573		)	—			(573		)
Dividends declared on preferred and preference stock	—		—			—			(94		)	—			(94		)
Stock-based compensation	—		—			—			(36		)	—			(36		)
Noncash stock-based compensation	—		8			—			—			—			8
Issuance of preference stock	—		(12		)	—			—			475			463
Redemption of preference stock	—		15			—			(15		)	(475		)	(475		)
Balance at September 30, 2017	$	2,168	$	668		$	(18	)	$	9,930		$	2,245		$	14,993

Variable Interest Entities

9 Months Ended

Sep. 30, 2018

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Variable Interest Entities

A variable interest entity ("VIE") is defined as a legal entity that meets one of two conditions: (1) the equity owners do not have sufficient equity at risk, or (2) the holders of the equity investment at risk, as a group, lack any of the following three characteristics: decision-making rights, the obligation to absorb losses, or the right to receive the expected residual returns of the entity. The primary beneficiary is identified as the variable interest holder that has both the power to direct the activities of the VIE that most significantly impact the entity's economic performance and the obligation to absorb losses or the right to receive benefits from the entity that could potentially be significant to the VIE. The primary beneficiary is required to consolidate the VIE. Commercial and operating activities are generally the factors that most significantly impact the economic performance of such VIEs. Commercial and operating activities include construction, operation and maintenance, fuel procurement, dispatch, and compliance with regulatory and contractual requirements.

Variable Interest in VIEs that are not Consolidated

Power Purchase Agreements

SCE has power purchase agreements ("PPAs") that are classified as variable interests in VIEs, including tolling agreements through which SCE provides the natural gas to fuel the plants and contracts with qualifying facilities 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. Since 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 involvement with VIEs result from amounts due under the PPAs. Under these contracts, SCE recovers the costs incurred through demonstration of compliance with its California Public Utilities Commission ("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 11 of the 2017 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 from these VIE projects was 3,602 MW and 4,858 MW at September 30, 2018 and 2017, respectively, and the amounts that SCE paid to these projects were $328 million and $325 million for the three months ended September 30, 2018 and 2017, respectively, and $567 million and $571 million for nine months ended September 30, 2018 and 2017, respectively. These amounts are recoverable in customer rates, subject to reasonableness review.

Unconsolidated Trusts of SCE

SCE Trust II, Trust III, Trust IV, Trust V, and Trust VI were formed in 2013, 2014, 2015, 2016, and 2017, respectively, for the exclusive purpose of issuing the 5.10%, 5.75%, 5.375%, 5.45%, and 5.00% 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. SCE Trust II, Trust III, Trust IV, Trust V and Trust VI issued to the public trust securities in the face amounts of $400 million, $275 million, $325 million, $300 million, and $475 million (cumulative, liquidation amounts of $25 per share), respectively, and $10,000 of common stock each to SCE. The trusts invested the proceeds of these trust securities in Series G, Series H, Series J, Series K, and Series L Preference Stock issued by SCE in the principal amounts of $400 million, $275 million, $325 million, $300 million, and $475 million (cumulative, $2,500 per share liquidation values), respectively, which have substantially the same payment terms as the respective trust securities.

The Series G, Series H, Series J, Series K, and Series L Preference Stock and the corresponding trust securities do not have a maturity date. Upon any redemption of any shares of the Series G, Series H, Series J, Series K, or Series L Preference Stock, a corresponding dollar amount of trust securities will be redeemed by the applicable trust. The applicable trust will make distributions at the same rate and on the same dates on the applicable series of trust securities if and when the SCE board of directors declares and makes dividend payments on the related Preference Stock. The applicable trust will use any dividends it receives on the related Preference Stock to make its corresponding distributions on the applicable series of trust securities. If SCE does not make a dividend payment to any of these trusts, 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 related Preference Stock.

SCE formed Trust I, a VIE, in 2012 for the exclusive purpose of issuing 5.625% trust preference securities. SCE Trust I issued trust securities in the face amounts of $475 million to the public and $10,000 of common stock to SCE. SCE Trust I invested the proceeds of these trust securities in Series F Preference Stock issued by SCE in the principal amount of $475 million. In July 2017, all of the outstanding Series F Preference Stock was redeemed, and accordingly, SCE Trust I redeemed $475 million of trust securities from the public and $10,000 of common stock from SCE. As a result in September 2017, SCE Trust I was terminated.

The Trust II, Trust III, Trust IV, Trust V and Trust VI balance sheets as of September 30, 2018 and December 31, 2017, consisted of investments of $400 million, $275 million, $325 million, $300 million, and $475 million in the Series G, Series H, Series J, Series K and Series L Preference Stock, respectively, $400 million, $275 million, $325 million, $300 million, and $475 million of trust securities, respectively, and $10,000 each of common stock.

The following table provides a summary of the trusts' income statements:



	Three months ended September 30,
(in millions)	Trust I		Trust II		Trust III		Trust IV		Trust V		Trust VI
2018
Dividend income	*		$	5	$	4	$	4	$	4	$	6
Dividend distributions	*		5		4		4		4		6
2017
Dividend income	$	1	$	5	$	4	$	4	$	4	$	6
Dividend distributions	1		5		4		4		4		6



	Nine months ended September 30,
(in millions)	Trust I		Trust II		Trust III		Trust IV		Trust V		Trust VI
2018
Dividend income	*		$	15	$	12	$	13	$	12	$	18
Dividend distributions	*		15		12		13		12		18
2017
Dividend income	$	14	$	15	$	12	$	13	$	12	$	6
Dividend distributions	14		15		12		13		12		6

* Not applicable

Fair Value Measurements

9 Months Ended

Sep. 30, 2018

Fair Value Disclosures [Abstract]

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, 2018 and December 31, 2017, 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.

Level 1 – The fair value of Edison International's 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, U.S. treasury securities, mutual funds, and money market funds.

Level 2 – Edison International's and SCE's Level 2 assets and liabilities include fixed income securities, primarily consisting of U.S. government and agency bonds, municipal bonds and corporate bonds, 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.

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 an exchange (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 derivative contracts that trade infrequently such as congestion revenue rights ("CRRs"). Edison International Parent and Other does not have any Level 3 assets and liabilities.

Assumptions are made in order to value derivative contracts in which observable inputs are not available. 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. See Note 6 for a discussion of derivative instruments.

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, 2018
(in millions)	Level 1		Level 2		Level 3		Netting and Collateral¹			Total
Assets at fair value
Derivative contracts	$	—	$	56	$	31	$	(8	)	$	79
Other	15		21		—		—			36
Nuclear decommissioning trusts:
Stocks²	1,600		—		—		—			1,600
Fixed Income³	1,025		1,651		—		—			2,676
Short-term investments, primarily cash equivalents	144		92		—		—			236
Subtotal of nuclear decommissioning trusts⁴	2,769		1,743		—		—			4,512
Total assets	2,784

Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Discounts and issuance costs of long term debt	$ (63)	$ 1
Southern California Edison Company
Discounts and issuance costs of long term debt	$ (58)	$ 10