Compensation and Benefit Plans (Expenses) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pension Plans
Pension and Other Postretirement Benefits
Service cost	$ 130	$ 121	$ 114
Non-service cost (benefit)
Interest cost	103	124	155
Expected return on plan assets	(222)	(215)	(205)
Amortization of prior service cost	1	2	2
Amortization of net (gain) loss	11	10	7
Regulatory adjustment	25	16	(3)
Total non-service benefit	(82)	(63)	(44)
Total expense recognized	48	58	70
Postretirement Benefits Other Than Pensions
Pension and Other Postretirement Benefits
Service cost	40	38	30
Non-service cost (benefit)
Interest cost	52	63	77
Expected return on plan assets	(106)	(119)	(111)
Amortization of prior service cost	(1)	(1)	(1)
Amortization of net (gain) loss	(35)	(29)	(17)
Regulatory adjustment	51	49	29
Total non-service benefit	(39)	(37)	(23)
Total expense	1	1	7
SCE
Non-service cost (benefit)
Total non-service benefit	(123)	(102)	(70)
SCE | Pension Plans
Pension and Other Postretirement Benefits
Service cost	127	119	111
Non-service cost (benefit)
Interest cost	95	114	143
Expected return on plan assets	(211)	(203)	(194)
Amortization of prior service cost	1	1	2
Amortization of net (gain) loss	7	7	5
Regulatory adjustment	25	16	(3)
Total non-service benefit	(83)	(65)	(47)
Total expense recognized	44	54	64
SCE | Postretirement Benefits Other Than Pensions
Pension and Other Postretirement Benefits
Service cost	40	37	30
Non-service cost (benefit)
Interest cost	52	63	77
Expected return on plan assets	(106)	(119)	(111)
Amortization of prior service cost	(1)	(1)	(1)
Amortization of net (gain) loss	(36)	(29)	(17)
Regulatory adjustment	51	49	29
Total non-service benefit	$ (40)	$ (37)	(23)
Total expense			$ 7