Equity (Quarter) (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended
	Mar. 31, 2021	Sep. 30, 2021	Sep. 30, 2021	May 31, 2019
Class of Stock [Line Items]
Equity contribution	$ 575
Series A Preferred Stock, 5.375%
Class of Stock [Line Items]
Stock issued (in shares)	1,250,000
Proceeds received, net of offering costs	$ 1,200
Preferred Stock, dividend rate, (as a percent)	5.375%
Liquidation value (in dollars per share)	$ 1,000
Dividend reset period	5 years
Margin rate for dividend rate reset (as a percent)	4.698%
Redemption amount (in dollars per share)	$ 1,000
Redemption amount following change in criteria (in dollars per share)	$ 1,020
SCE
Class of Stock [Line Items]
Capital contributions		$ 83	$ 1,300
At-the-market Program (ATM)
Class of Stock [Line Items]
Stock issued (in shares)		0	0
Aggregate sale price				$ 1,500
Aggregate sales price remaining		$ 1,300	$ 1,300
401(K)
Class of Stock [Line Items]
Stock issued (in shares)		52,100	465,400
Proceeds received, net of offering costs		$ 3	$ 27
Stock compensation awards
Class of Stock [Line Items]
Stock issued (in shares)		54,970	267,564
Proceeds received, net of offering costs		$ 2	$ 7
In lieu of dividend payment
Class of Stock [Line Items]
Stock issued (in shares)		77,468	225,383
Proceeds received, net of offering costs		$ 5	$ 13
Optional cash investments | Edison International
Class of Stock [Line Items]
Stock issued (in shares)			21,792
Proceeds received, net of offering costs			$ 1