Summary of Significant Accounting Policies (SCE Dividends) (Details) - SCE - USD ($) $ in Millions			12 Months Ended
	Feb. 24, 2022	Jan. 01, 2020	Dec. 31, 2019	Dec. 31, 2018
Significant Accounting Policies [Line Items]
Weighted-average equity component authorization (as a percent)		52.00%	48.00%	45.20%
Spot rate equity ratio				47.70%
Weighted-average common equity component authorization, set by CPUC remaining over number of months (in months)			37 months	37 months
Waiver threshold percent				47.70%
Weighted-average common equity component of total capitalization percent (below)				48.70%
Wildfire related charge incurred after tax				$ 1,800
Dividends	$ 325