Regulatory Assets and Liabilities (Schedule of Regulatory Liabilities) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Regulatory Liabilities [Line Items]
Current regulatory liabilities	$ 767		$ 767		$ 1,532
Long-term regulatory liabilities	8,685		8,685		8,329
Deferred tax re-measurement	0	$ 0	69	$ 0
Southern California Edison
Regulatory Liabilities [Line Items]
Current regulatory liabilities	767		767		1,532
Long-term regulatory liabilities	8,685		8,685		8,329
Total regulatory liabilities	9,452		9,452		9,861
Deferred tax re-measurement	0	$ 0	69	$ 0
Southern California Edison | Regulatory balancing accounts
Regulatory Liabilities [Line Items]
Current regulatory liabilities	728		728		1,080
Long-term regulatory liabilities	1,591		1,591		1,344
Southern California Edison | Energy derivatives
Regulatory Liabilities [Line Items]
Current regulatory liabilities	24		24		158
Southern California Edison | 2018 GRC
Regulatory Liabilities [Line Items]
Current regulatory liabilities	0		0		274
Southern California Edison | Other
Regulatory Liabilities [Line Items]
Current regulatory liabilities	15		15		20
Long-term regulatory liabilities	179		179		125
Southern California Edison | Cost of removal
Regulatory Liabilities [Line Items]
Long-term regulatory liabilities	2,737		2,737		2,769
Southern California Edison | Re-measurement of deferred taxes
Regulatory Liabilities [Line Items]
Long-term regulatory liabilities	2,530		2,530		2,776
Southern California Edison | Recoveries in excess of ARO liabilities
Regulatory Liabilities [Line Items]
Long-term regulatory liabilities	1,454		1,454		1,130
Southern California Edison | Other postretirement benefits
Regulatory Liabilities [Line Items]
Long-term regulatory liabilities	$ 194		$ 194		$ 185