Variable Interest Entities (Trusts) (Details)	12 Months Ended
	Dec. 31, 2021 USD ($) MW	Dec. 31, 2020 USD ($) MW	Dec. 31, 2017 USD ($) $ / shares	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2018 USD ($)
Variable Interest Entity [Line Items]
Redemption of trust securities		$ 308,000,000
SCE
Variable Interest Entity [Line Items]
Redemption of trust securities		308,000,000
SCE | Trust Securities [Member]
Variable Interest Entity [Line Items]
Liquidation value (in dollars per share) | $ / shares			$ 2,500
SCE | 5.10% Series G Preferred Stock
Variable Interest Entity [Line Items]
Security dividend rate, (as a percent)	5.10%
Redemption of trust securities		180,000,000
SCE | 5.75% Series H Preferred Stock
Variable Interest Entity [Line Items]
Security dividend rate, (as a percent)	5.75%
SCE | 5.375% Series J Preferred Stock
Variable Interest Entity [Line Items]
Security dividend rate, (as a percent)	5.375%
SCE | 5.45% Series K Preferred Stock
Variable Interest Entity [Line Items]
Security dividend rate, (as a percent)	5.45%
SCE | 5.00% Series L Preferred Stock
Variable Interest Entity [Line Items]
Security dividend rate, (as a percent)	5.00%
SCE | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Liquidation value (in dollars per share) | $ / shares			$ 25
Common stock	$ 10,000	$ 10,000	$ 10,000
SCE | Power Purchase Agreement
Variable Interest Entity [Line Items]
Power generating capacity for majority interest (in megawatts) | MW	3,545	5,103
Amount of related party transaction	$ 673,000,000	$ 744,000,000
SCE | Trust II
Variable Interest Entity [Line Items]
Liquidation preference							$ 400,000,000
SCE | Trust II | Trust Securities [Member]
Variable Interest Entity [Line Items]
Liquidation preference	220,000,000	220,000,000
SCE | Trust II | 5.10% Series G Preferred Stock
Variable Interest Entity [Line Items]
Security dividend rate, (as a percent)							5.10%
Liquidation preference	220,000,000	220,000,000					$ 400,000,000
SCE | Trust III
Variable Interest Entity [Line Items]
Liquidation preference						$ 275,000,000
SCE | Trust III | Trust Securities [Member]
Variable Interest Entity [Line Items]
Liquidation preference	275,000,000	275,000,000
SCE | Trust III | 5.75% Series H Preferred Stock
Variable Interest Entity [Line Items]
Security dividend rate, (as a percent)						5.75%
Liquidation preference	275,000,000	275,000,000				$ 275,000,000
SCE | Trust IV
Variable Interest Entity [Line Items]
Liquidation preference					$ 325,000,000
SCE | Trust IV | Trust Securities [Member]
Variable Interest Entity [Line Items]
Liquidation preference	325,000,000	325,000,000
SCE | Trust IV | 5.375% Series J Preferred Stock
Variable Interest Entity [Line Items]
Security dividend rate, (as a percent)					5.375%
Liquidation preference	325,000,000	325,000,000			$ 325,000,000
SCE | Trust V
Variable Interest Entity [Line Items]
Liquidation preference				$ 300,000,000
SCE | Trust V | Trust Securities [Member]
Variable Interest Entity [Line Items]
Liquidation preference	300,000,000	300,000,000
SCE | Trust V | 5.45% Series K Preferred Stock
Variable Interest Entity [Line Items]
Security dividend rate, (as a percent)				5.45%
Liquidation preference	300,000,000	300,000,000		$ 300,000,000
SCE | Trust VI
Variable Interest Entity [Line Items]
Liquidation preference								$ 475,000,000
SCE | Trust VI | Trust Securities [Member]
Variable Interest Entity [Line Items]
Liquidation preference	475,000,000	475,000,000						$ 475,000,000
SCE | Trust VI | 5.00% Series L Preferred Stock
Variable Interest Entity [Line Items]
Security dividend rate, (as a percent)			5.00%
Liquidation preference	$ 475,000,000	$ 475,000,000