Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Allowance for uncollectible amounts
Movement in Valuation and Qualifying Accounts
Balance at Beginning of Period	$ 188.0	$ 49.0	$ 51.0
Charged to Costs and Expenses	44.0	46.0	32.0
Charged to Other Accounts	91.0	120.0	0.0
Deductions	14.0	27.0	34.0
Balance at End of Period	309.0	188.0	49.0
Allowance for uncollectible amounts | Customers
Movement in Valuation and Qualifying Accounts
Balance at Beginning of Period	175.0	35.0	31.0
Charged to Costs and Expenses	33.0	36.0	22.0
Charged to Other Accounts	91.0	120.0	0.0
Deductions	6.0	16.0	18.0
Balance at End of Period	293.0	175.0	35.0
Allowance for uncollectible amounts | All others
Movement in Valuation and Qualifying Accounts
Balance at Beginning of Period	13.0	14.0	20.0
Charged to Costs and Expenses	11.0	10.0	10.0
Charged to Other Accounts	0.0	0.0	0.0
Deductions	8.0	11.0	16.0
Balance at End of Period	16.0	13.0	14.0
Tax valuation allowance
Movement in Valuation and Qualifying Accounts
Balance at Beginning of Period	35.0	35.0	36.0
Charged to Costs and Expenses	9.0	0.0	0.0
Charged to Other Accounts	0.0	0.0	0.0
Deductions	0.0	0.0	1.0
Balance at End of Period	44.0	35.0	35.0
Tax valuation allowance | Operating loss carryforward
Movement in Valuation and Qualifying Accounts
Valuation allowance increase (decrease)	3.0
Tax valuation allowance | Charitable contribution carryover
Movement in Valuation and Qualifying Accounts
Valuation allowance increase (decrease)	6.0
SCE | Allowance for uncollectible amounts
Movement in Valuation and Qualifying Accounts
Balance at Beginning of Period	188.0	49.0	51.0
Charged to Costs and Expenses	44.0	46.0	32.0
Charged to Other Accounts	91.0	120.0	0.0
Deductions	14.0	27.0	34.0
Balance at End of Period	309.0	188.0	49.0
SCE | Allowance for uncollectible amounts | Customers
Movement in Valuation and Qualifying Accounts
Balance at Beginning of Period	175.0	35.0	31.0
Charged to Costs and Expenses	33.0	36.0	22.0
Charged to Other Accounts	91.0	120.0	0.0
Deductions	6.0	16.0	18.0
Balance at End of Period	293.0	175.0	35.0
SCE | Allowance for uncollectible amounts | All others
Movement in Valuation and Qualifying Accounts
Balance at Beginning of Period	13.0	14.0	20.0
Charged to Costs and Expenses	11.0	10.0	10.0
Charged to Other Accounts	0.0	0.0	0.0
Deductions	8.0	11.0	16.0
Balance at End of Period	16.0	$ 13.0	$ 14.0
SCE | Tax valuation allowance
Movement in Valuation and Qualifying Accounts
Charged to Costs and Expenses	6.0
Charged to Other Accounts	0.0
Deductions	0.0
Balance at End of Period	6.0
SCE | Tax valuation allowance | Charitable contribution carryover
Movement in Valuation and Qualifying Accounts
Valuation allowance increase (decrease)	$ 6.0