Revenue (Summary) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Revenue
Total operating revenue		$ 5,299	$ 4,644	$ 11,574	$ 10,421
SCE
Revenue
Revenues from contracts with customers		5,064	4,220	11,089	9,440
Alternative revenue programs and other operating revenue		229	415	463	955
Total operating revenue		5,293	4,635	11,552	10,395
Approved regulatory increase (decrease)	$ 505
Receivables from contracts with customers		2,800		2,800		$ 1,500
Accrued unbilled revenues		1,100		1,100		$ 521
SCE | Earning Activities
Revenue
Revenues from contracts with customers		2,260	1,893	5,667	5,175
Alternative revenue programs and other operating revenue		135	233	325	467
Total operating revenue		2,395	2,126	5,992	5,642
SCE | Cost- Recovery Activities
Revenue
Revenues from contracts with customers		2,804	2,327	5,422	4,265
Alternative revenue programs and other operating revenue		94	182	138	488
Total operating revenue		2,898	$ 2,509	5,560	$ 4,753
2021 General Rate Case | SCE
Revenue
Approved regulatory increase (decrease)		$ 404		$ 1,000