Variable Interest Entities (Textual) (Details)	1 Months Ended	3 Months Ended		6 Months Ended
	Jul. 27, 2017 USD ($)	Jun. 30, 2017 USD ($) $ / shares MW	Jun. 30, 2016 USD ($) MW	Jun. 30, 2017 USD ($) $ / shares MW	Jun. 30, 2016 USD ($) MW
Variable Interest Entity
Redemption of preference stock					$ 125,000,000
Southern California Edison
Variable Interest Entity
Redemption of preference stock					$ 125,000,000
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | SCE Power Purchase Contracts
Variable Interest Entity
Power generating capacity (in megawatts) | MW		4,900	4,349	4,900	4,349
Payments to unconsolidated VIEs for power purchase contracts		$ 106,000,000	$ 92,000,000	$ 246,000,000	$ 219,000,000
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust I
Variable Interest Entity
Common stock		10,000		$ 10,000
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust I | Trust Securities
Variable Interest Entity
Security dividend rate				5.625%
Liquidation preference		$ 475,000,000		$ 475,000,000
Liquidation value (in dollars per share) | $ / shares		$ 25		$ 25
Common stock		$ 10,000		$ 10,000
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust I | Trust Securities | Subsequent event
Variable Interest Entity
Redemption of preference stock	$ 10,000
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust I | Series F Preferred Stock
Variable Interest Entity
Security dividend rate				5.625%
Liquidation preference		$ 475,000,000		$ 475,000,000
Liquidation value (in dollars per share) | $ / shares		$ 2,500		$ 2,500
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust II
Variable Interest Entity
Common stock		$ 10,000		$ 10,000
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust II | Trust Securities
Variable Interest Entity
Security dividend rate				5.10%
Liquidation preference		$ 400,000,000		$ 400,000,000
Liquidation value (in dollars per share) | $ / shares		$ 25		$ 25
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust II | Series G Preferred Stock
Variable Interest Entity
Security dividend rate				5.10%
Liquidation preference		$ 400,000,000		$ 400,000,000
Liquidation value (in dollars per share) | $ / shares		$ 2,500		$ 2,500
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust III
Variable Interest Entity
Common stock		$ 10,000		$ 10,000
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust III | Trust Securities
Variable Interest Entity
Security dividend rate				5.75%
Liquidation preference		$ 275,000,000		$ 275,000,000
Liquidation value (in dollars per share) | $ / shares		$ 25		$ 25
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust III | Series H Preferred Stock
Variable Interest Entity
Security dividend rate				5.75%
Liquidation preference		$ 275,000,000		$ 275,000,000
Liquidation value (in dollars per share) | $ / shares		$ 2,500		$ 2,500
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust IV
Variable Interest Entity
Common stock		$ 10,000		$ 10,000
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust IV | Trust Securities
Variable Interest Entity
Security dividend rate				5.375%
Liquidation preference		$ 325,000,000		$ 325,000,000
Liquidation value (in dollars per share) | $ / shares		$ 25		$ 25
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust IV | Series J Preferred Stock
Variable Interest Entity
Security dividend rate				5.375%
Liquidation preference		$ 325,000,000		$ 325,000,000
Liquidation value (in dollars per share) | $ / shares		$ 2,500		$ 2,500
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust V
Variable Interest Entity
Common stock		$ 10,000		$ 10,000
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust V | Trust Securities
Variable Interest Entity
Security dividend rate				5.45%
Liquidation preference		$ 300,000,000		$ 300,000,000
Liquidation value (in dollars per share) | $ / shares		$ 25		$ 25
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust V | Series K Preferred Stock
Variable Interest Entity
Security dividend rate				5.45%
Liquidation preference		$ 300,000,000		$ 300,000,000
Liquidation value (in dollars per share) | $ / shares		$ 2,500		$ 2,500
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust VI
Variable Interest Entity
Common stock		$ 10,000		$ 10,000
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust VI | Trust Securities
Variable Interest Entity
Security dividend rate				5.00%
Liquidation preference		$ 475,000,000		$ 475,000,000
Liquidation value (in dollars per share) | $ / shares		$ 25		$ 25
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust VI | Trust Securities | Subsequent event
Variable Interest Entity
Redemption of preference stock	$ 475,000,000
Southern California Edison | Variable Interest Entity, Not Primary Beneficiary | Trust VI | Series L Preferred Stock
Variable Interest Entity
Security dividend rate				5.00%
Liquidation preference		$ 475,000,000		$ 475,000,000
Liquidation value (in dollars per share) | $ / shares		$ 2,500		$ 2,500