- REGULATORY ACCOUNTS (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Net Regulatory Assets (Liabilities) Sempra Energy Consolidated [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	$ (2,697)	$ (2,189)
San Diego Gas and Electric Company [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Regulatory balancing accounts - net undercollected, Noncurrent	79	63
San Diego Gas and Electric Company [Member] | Fixed-price contracts and other derivatives [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	47	96
San Diego Gas and Electric Company [Member] | Deferred income taxes (refundable) recoverable in rates [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(267)	(281)
San Diego Gas and Electric Company [Member] | Pension and other postretirement benefit plan obligations [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	130	153
San Diego Gas and Electric Company [Member] | Removal obligations [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(1,894)	(1,846)
San Diego Gas and Electric Company [Member] | Unamortized loss on reacquired debt [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	7	9
San Diego Gas and Electric Company [Member] | Environmental costs [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	28	29
San Diego Gas and Electric Company [Member] | Sunrise Powerlink fire mitigation [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	119	119
San Diego Gas and Electric Company [Member] | Regulatory Balancing Accounts, Commodity – electric [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	23	82
San Diego Gas and Electric Company [Member] | Regulatory Balancing Accounts, Gas transportation [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	22	22
San Diego Gas and Electric Company [Member] | Regulatory Balancing Accounts, Safety and reliability [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	64	48
San Diego Gas and Electric Company [Member] | Regulatory Balancing Accounts, Public purpose programs [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(73)	(70)
San Diego Gas and Electric Company [Member] | Regulatory Balancing Accounts, Other balancing accounts [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	30	233
San Diego Gas and Electric Company [Member] | Other regulatory (liabilities) assets [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(152)	(70)
San Diego Gas and Electric Company [Member] | Net Regulatory Assets (Liabilities) SDGE [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(1,916)	(1,476)
Southern California Gas Company [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Regulatory balancing accounts - net undercollected, Noncurrent	236	118
Southern California Gas Company [Member] | Deferred income taxes (refundable) recoverable in rates [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(383)	(437)
Southern California Gas Company [Member] | Pension and other postretirement benefit plan obligations [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	378	513
Southern California Gas Company [Member] | Employee benefit costs [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	45	45
Southern California Gas Company [Member] | Removal obligations [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(868)	(924)
Southern California Gas Company [Member] | Unamortized loss on reacquired debt [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	7	8
Southern California Gas Company [Member] | Environmental costs [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	24	22
Southern California Gas Company [Member] | Workers’ compensation [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	9	12
Southern California Gas Company [Member] | Regulatory Balancing Accounts, Commodity - gas including transportation
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	139	151
Southern California Gas Company [Member] | Regulatory Balancing Accounts, Safety and reliability [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	312	266
Southern California Gas Company [Member] | Regulatory Balancing Accounts, Public purpose programs [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(276)	(274)
Southern California Gas Company [Member] | Regulatory Balancing Accounts, Other balancing accounts [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(147)	(114)
Southern California Gas Company [Member] | Other regulatory (liabilities) assets [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(110)	(64)
Southern California Gas Company [Member] | Net Regulatory Assets (Liabilities) SoCalGas [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(870)	(796)
Sempra Mexico [Member] | Deferred income taxes (refundable) recoverable in rates [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	83	83
Sempra Mexico [Member] | Other regulatory assets [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	$ 6	$ 0