Fair Value Measurements (Textual) (Details) - USD ($)	3 Months Ended
	Jun. 30, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds		$ 31,000,000		$ 62,000,000
Edison Energy Group
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Goodwill impairment	$ 34,000,000	25,000,000	$ 19,000,000
Goodwill impairment after-tax	$ 25,000,000	18,000,000	$ 13,000,000
Edison International Parent and Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments		0
Edison International Parent and Other | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds		$ 31,000,000		24,000,000
Edison International Parent and Other | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments				$ 5,000,000