Schedule I - Condensed Financial Information of Parent (Details)		1 Months Ended	3 Months Ended								9 Months Ended	12 Months Ended
	Jan. 01, 2020 USD ($)	May 31, 2020 USD ($) shares	Dec. 31, 2020 USD ($) shares	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($)	Dec. 31, 2020 USD ($)	Apr. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)	May 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Assets:
Cash and cash equivalents	$ 68,000,000		$ 87,000,000			$ 68,000,000	$ 68,000,000					$ 87,000,000	$ 68,000,000		$ 87,000,000		$ 68,000,000
Other current assets															224,000,000		188,000,000
Total current assets															5,061,000,000		3,560,000,000
Other long-term assets															860,000,000		648,000,000
Total assets															69,372,000,000		64,382,000,000
Liabilities and equity:
Short-term debt															2,398,000,000		550,000,000
Current portion of long-term debt															1,029,000,000		479,000,000
Other current liabilities															1,612,000,000		1,388,000,000
Total current liabilities															10,277,000,000		5,523,000,000
Long-term debt															19,632,000,000		17,864,000,000
Total equity															15,949,000,000		15,496,000,000		$ 12,652,000,000	$ 13,866,000,000
Total liabilities and equity															$ 69,372,000,000		64,382,000,000
Condensed Statements of Income:
Interest income from affiliates			3,157,000,000	$ 4,644,000,000	$ 2,987,000,000	2,790,000,000	2,970,000,000	$ 3,741,000,000	$ 2,812,000,000	$ 2,824,000,000		13,578,000,000	12,347,000,000	$ 12,657,000,000
Operating, interest and other expenses												12,361,000,000	10,572,000,000	13,209,000,000
Operating income (loss)			794,000,000	(379,000,000)	500,000,000	302,000,000	287,000,000	636,000,000	500,000,000	352,000,000		1,217,000,000	1,775,000,000	(552,000,000)
Income tax benefit												(305,000,000)	(278,000,000)	(739,000,000)
Income (loss) from continuing operations												871,000,000	1,405,000,000	(350,000,000)
Income from discontinued operations, net of tax												0	0	34,000,000
Net income (loss)												739,000,000	1,284,000,000	(423,000,000)
Condensed Statements of Comprehensive Income
Net income (loss)												739,000,000	1,284,000,000	(423,000,000)
Other comprehensive loss, net of tax												0	(9,000,000)	(7,000,000)
Comprehensive income (loss) attributable to Edison International												739,000,000	1,275,000,000	(430,000,000)
Condensed Statements of Cash Flows:
Net cash provided by operating activities												1,263,000,000	(307,000,000)	3,177,000,000
Cash flows from financing activities:
Long-term debt issued												3,073,000,000	3,696,000,000	3,237,000,000
Long-term debt repaid or repurchased												(1,099,000,000)	(82,000,000)	(654,000,000)
Short-term debt borrowed												2,994,000,000	1,750,000,000	0
Repayments of Short-term Debt												(1,126,000,000)	(1,750,000,000)	0
Common stock issued												912,000,000	2,391,000,000	0
Commercial paper and other short-term borrowing (repayments), net												304,000,000	(172,000,000)	(1,611,000,000)
Dividends paid												(928,000,000)	(810,000,000)	(788,000,000)
Net cash provided by financing activities												3,727,000,000	4,903,000,000	82,000,000
Net cash used in investing activities												(4,971,000,000)	(4,678,000,000)	(4,239,000,000)
Cash and cash equivalents, beginning of year	68,000,000					68,000,000						68,000,000
Cash and cash equivalents, end of year			87,000,000				68,000,000					87,000,000	68,000,000
Debt and Credit Agreements
Debt covenant capitalization ratio															0.70
Actual debt to capitalization ratio															0.59
Revolving Credit Facility
Short-term Debt, Other Disclosures [Abstract]
Commitment															$ 6,800,000,000
Outstanding borrowings															1,350,000,000
Amount available															$ 5,291,000,000
Senior notes | 4.125% senior notes due in 2028
Debt and Credit Agreements
Interest rate on debt (as a percent)															4.125%
Senior notes															$ 550,000,000
SCE
Assets:
Cash and cash equivalents	24,000,000		55,000,000			24,000,000	24,000,000					24,000,000	24,000,000		55,000,000		24,000,000
Other current assets															216,000,000		184,000,000
Total current assets															5,017,000,000		3,530,000,000
Other long-term assets															843,000,000		595,000,000
Total assets															69,286,000,000		64,273,000,000
Liabilities and equity:
Short-term debt															2,268,000,000		550,000,000
Current portion of long-term debt															1,029,000,000		79,000,000
Other current liabilities															1,294,000,000		1,298,000,000
Total current liabilities															9,831,000,000		5,059,000,000
Long-term debt															16,499,000,000		15,132,000,000
Total equity															18,650,000,000		17,827,000,000		13,785,000,000	14,672,000,000
Total liabilities and equity															$ 69,286,000,000		64,273,000,000
Condensed Statements of Income:
Interest income from affiliates			3,151,000,000	4,635,000,000	2,980,000,000	2,780,000,000	2,958,000,000	3,732,000,000	2,800,000,000	2,816,000,000		13,546,000,000	12,306,000,000	12,611,000,000
Operating, interest and other expenses												12,368,000,000	10,461,000,000	13,017,000,000
Operating income (loss)			678,000,000	$ (364,000,000)	$ 548,000,000	316,000,000	325,000,000	$ 649,000,000	$ 513,000,000	358,000,000		1,178,000,000	1,845,000,000	(406,000,000)
Income tax benefit												(277,000,000)	(229,000,000)	(696,000,000)
Condensed Statements of Comprehensive Income
Other comprehensive loss, net of tax												(2,000,000)	(11,000,000)	(4,000,000)
Condensed Statements of Cash Flows:
Net cash provided by operating activities												1,427,000,000	(91,000,000)	3,191,000,000
Cash flows from financing activities:
Long-term debt issued												2,676,000,000	2,306,000,000	2,692,000,000
Long-term debt repaid or repurchased												(699,000,000)	(82,000,000)	(639,000,000)
Short-term debt borrowed												2,194,000,000	750,000,000	0
Repayments of Short-term Debt												(326,000,000)	(750,000,000)	0
Commercial paper and other short-term borrowing (repayments), net												175,000,000	(171,000,000)	(520,000,000)
Dividends paid												(1,450,000,000)	(521,000,000)	(909,000,000)
Net cash provided by financing activities												3,699,000,000	4,771,000,000	616,000,000
Net cash used in investing activities												(5,094,000,000)	(4,678,000,000)	$ (4,300,000,000)
Cash and cash equivalents, beginning of year	$ 24,000,000					24,000,000						24,000,000
Cash and cash equivalents, end of year			55,000,000				24,000,000					55,000,000	$ 24,000,000
Basis of Presentation
Minimum percentage of weighted-average common equity component authorization, set by CPUC (as a percent)	52.00%												48.00%	45.20%
Wildfire related charge incurred after tax														$ 1,800,000,000
Weighted-average common equity component of total capitalization percent with CPUC waiver														48.70%
Waiver threshold percent (as a percent)														47.70%
Debt and Credit Agreements
Debt covenant capitalization ratio															0.65
Actual debt to capitalization ratio															0.51
Related Party Transactions
Insurance receivable from affiliate															$ 268,000,000		0
SCE | Revolving Credit Facility
Short-term Debt, Other Disclosures [Abstract]
Commitment															5,300,000,000
Outstanding borrowings															1,220,000,000
Amount available															3,921,000,000
SCE | Term loan credit agreement
Debt and Credit Agreements
Debt, face amount															475,000,000
SCE | Multi-year credit facilities
Short-term Debt, Other Disclosures [Abstract]
Commitment															3,000,000,000
Outstanding borrowings															725,000,000
Amount available															2,116,000,000
Edison International | Revolving Credit Facility
Short-term Debt, Other Disclosures [Abstract]
Commitment															1,500,000,000
Outstanding borrowings															130,000,000
Amount available															$ 1,370,000,000
Edison International | Multi-year credit facilities | Revolving Credit Facility
Debt and Credit Agreements
Weighted average interest rate (as a percent)															0.42%
Short-term Debt, Other Disclosures [Abstract]
Commitment															$ 1,500,000,000
Outstanding borrowings															130,000,000
Amount available															1,370,000,000
EME | Affiliated Entity
Related Party Transactions
Net proceeds												132,000,000
Edison International Parent and Other
Liabilities and equity:
Current portion of long-term debt															0		400,000,000
Long-term debt															3,133,000,000		2,732,000,000
Edison International Parent and Other | Multi-year credit facilities
Short-term Debt, Other Disclosures [Abstract]
Outstanding borrowings																	0
Edison International Parent
Assets:
Cash and cash equivalents	$ 15,000,000		3,000,000			15,000,000	15,000,000			97,000,000	$ 97,000,000	15,000,000	$ 97,000,000	$ 97,000,000	3,000,000		15,000,000		$ 97,000,000	$ 524,000,000
Other current assets															43,000,000		260,000,000
Total current assets															46,000,000		275,000,000
Investments in subsidiaries															17,706,000,000		16,530,000,000
Deferred income taxes															675,000,000		608,000,000
Other long-term assets															71,000,000		76,000,000
Total assets															18,498,000,000		17,489,000,000
Liabilities and equity:
Short-term debt															129,000,000		0
Current portion of long-term debt															0		400,000,000
Other current liabilities															636,000,000		481,000,000
Total current liabilities															765,000,000		881,000,000
Long-term debt															3,133,000,000		2,733,000,000
Other long-term liabilities															552,000,000		572,000,000
Total equity															14,048,000,000		13,303,000,000
Total liabilities and equity															$ 18,498,000,000		17,489,000,000
Condensed Statements of Income:
Interest income from affiliates												1,000,000	5,000,000	0
Operating, interest and other expenses												189,000,000	150,000,000	98,000,000
Operating income (loss)												(188,000,000)	(145,000,000)	(98,000,000)
Equity in earnings (loss) of subsidiaries												851,000,000	1,385,000,000	(376,000,000)
Income (loss) before income taxes												663,000,000	1,240,000,000	(474,000,000)
Income tax benefit												(76,000,000)	(44,000,000)	(17,000,000)
Income (loss) from continuing operations												739,000,000	1,284,000,000	(457,000,000)
Income from discontinued operations, net of tax												0	0	34,000,000
Net income (loss)												739,000,000	1,284,000,000	(423,000,000)
Condensed Statements of Comprehensive Income
Net income (loss)												739,000,000	1,284,000,000	(423,000,000)
Other comprehensive loss, net of tax												0	(9,000,000)	(7,000,000)
Comprehensive income (loss) attributable to Edison International												739,000,000	1,275,000,000	(430,000,000)
Condensed Statements of Cash Flows:
Net cash provided by operating activities												1,171,000,000	181,000,000	785,000,000
Cash flows from financing activities:
Long-term debt issued												400,000,000	1,399,000,000	549,000,000
Long-term debt issuance costs												(3,000,000)	(9,000,000)	(4,000,000)
Long-term debt repaid or repurchased											0	(400,000,000)	0
Short-term debt borrowed												800,000,000	1,000,000,000	0
Repayments of Short-term Debt												(800,000,000)	(1,000,000,000)	0
Common stock issued												912,000,000	2,391,000,000	0
Payable due to affiliates												135,000,000	5,000,000	13,000,000
Commercial paper and other short-term borrowing (repayments), net												129,000,000	(1,000,000)	(1,141,000,000)
Payments for stock-based compensation												(3,000,000)	(27,000,000)	(24,000,000)
Receipts from stock option exercises												21,000,000	39,000,000	14,000,000
Dividends paid												(928,000,000)	(810,000,000)	(788,000,000)
Net cash provided by financing activities												263,000,000	2,987,000,000	(1,381,000,000)
Capital contributions to affiliate												(1,446,000,000)	(3,258,000,000)	(10,000,000)
Dividends from affiliate												0	8,000,000	179,000,000
Net cash used in investing activities												(1,446,000,000)	(3,250,000,000)	169,000,000
Net decrease in cash and cash equivalents												(12,000,000)	(82,000,000)	(427,000,000)
Cash and cash equivalents, beginning of year	$ 15,000,000					15,000,000				$ 97,000,000	$ 97,000,000	15,000,000	97,000,000	524,000,000
Cash and cash equivalents, end of year			$ 3,000,000				$ 15,000,000					3,000,000	15,000,000	97,000,000
Basis of Presentation
Cash dividends received from consolidated subsidiaries												1,300,000,000	400,000,000	788,000,000
Debt and Credit Agreements
Debt covenant capitalization ratio															0.70
Equity
Shares issued (in shares) | shares		14,181,882
Proceeds received		$ 800,000,000
Offering expenses		$ 14,000,000
Related Party Transactions
Insurance receivable from affiliate															$ 43,000,000		272,000,000
Current payables due to affiliates															323,000,000		198,000,000
Long-term insurance receivables due from affiliate															68,000,000		73,000,000
Long-term payables due to affiliates															$ 219,000,000		$ 213,000,000
Edison International Parent | Multi-year credit facilities
Debt and Credit Agreements
Weighted average interest rate (as a percent)															0.42%
Short-term Debt, Other Disclosures [Abstract]
Commitment															$ 1,500,000,000
Outstanding borrowings															130,000,000
Amount available															$ 1,370,000,000
Edison International Parent | Senior notes | 4.95% Senior notes due 2025
Debt and Credit Agreements
Debt, face amount																$ 400,000,000
Interest rate on debt (as a percent)																4.95%
Edison International Parent | Senior notes | 2.125% Senior notes due 2020
Debt and Credit Agreements
Interest rate on debt (as a percent)															2.125%	2.125%
Senior notes															$ 400,000,000	$ 400,000,000
Edison International Parent | Senior notes | 2.40% Senior notes due 2022
Debt and Credit Agreements
Interest rate on debt (as a percent)															2.40%
Senior notes															$ 400,000,000
Edison International Parent | Senior notes | 3.125% Senior notes due 2022
Debt and Credit Agreements
Interest rate on debt (as a percent)															3.125%
Senior notes															$ 300,000,000
Edison International Parent | Senior notes | 2.95% Senior notes due 2023
Debt and Credit Agreements
Interest rate on debt (as a percent)															2.95%
Senior notes															$ 400,000,000
Edison International Parent | Senior notes | 3.55% senior notes due 2024
Debt and Credit Agreements
Debt, face amount															$ 500,000,000
Interest rate on debt (as a percent)															3.55%
Edison International Parent | Senior notes | 5.75% senior notes due in 2027
Debt and Credit Agreements
Interest rate on debt (as a percent)															5.75%
Senior notes															$ 600,000,000
Edison International Parent | Senior notes | Term loan credit agreement
Debt and Credit Agreements
Debt, face amount						$ 800,000,000
Interest rate on debt (as a percent)						1.125%
Edison International Parent | SCE
Related Party Transactions
Expenses from services provided by SCE												2,000,000	2,000,000	2,000,000
Interest expense from loans due to affiliates												$ 4,000,000	$ 5,000,000	$ 5,000,000
Edison International Parent | ATM
Equity
Shares issued (in shares) | shares			0									391,501	2,824,261
Proceeds received												$ 27,000,000	$ 198,000,000
Offering expenses												300,000	2,000,000
Aggregate sale price (up to)																		$ 1,500,000,000
Aggregate sales price remaining															$ 1,300,000,000
Edison International Parent | 401(K)
Equity
Proceeds received												$ 99,000,000	$ 41,000,000
Issuance of new common stock (in shares) | shares												1,644,500	595,200
Edison International Parent | In lieu of dividend payment
Equity
Proceeds received												$ 17,000,000	$ 8,000,000
Issuance of new common stock (in shares) | shares												280,707	125,481
Edison International Parent | Internal Programs, Stock Compensation Awards
Equity
Proceeds received												$ 16,000,000	$ 22,000,000
Issuance of new common stock (in shares) | shares												387,425	423,569
Edison International Parent | Optional cash investments
Equity
Proceeds received												$ 2,000,000
Issuance of new common stock (in shares) | shares												35,999