REGULATORY MATTERS - REGULATORY ACCOUNTS (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Net Regulatory Assets (Liabilities) Sempra Energy Consolidated [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	$ (1,323)	$ (1,500)
San Diego Gas and Electric Company [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Regulatory balancing accounts - net undercollected, Noncurrent	331	139
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)	(88)	(53)
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)	72	22
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)	19	50
San Diego Gas and Electric Company [Member] | Removal obligations [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(2,228)	(2,121)
San Diego Gas and Electric Company [Member] | Environmental costs [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	55	56
San Diego Gas and Electric Company [Member] | Sunrise Powerlink fire mitigation [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	121	121
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)	85	72
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)	23	35
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)	60	67
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)	(138)	(158)
San Diego Gas and Electric Company [Member] | GRC retroactive impacts [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	14	56
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)	535	233
San Diego Gas and Electric Company [Member] | Other regulatory assets [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	110	72
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)	(1,360)	(1,548)
Southern California Gas Company [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Regulatory balancing accounts - net undercollected, Noncurrent	472	218
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)	9	(82)
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)	342	417
Southern California Gas Company [Member] | Employee benefit costs [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	37	37
Southern California Gas Company [Member] | Removal obligations [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(649)	(685)
Southern California Gas Company [Member] | Environmental costs [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	35	36
Southern California Gas Company [Member] | Regulatory Balancing Accounts, Commodity - gas including transportation [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(138)	(56)
Southern California Gas Company [Member] | Regulatory Balancing Accounts, Safety and reliability [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	299	335
Southern California Gas Company [Member] | Regulatory Balancing Accounts, Public purpose programs [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(274)	(253)
Southern California Gas Company [Member] | GRC retroactive impacts [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	51	202
Southern California Gas Company [Member] | Regulatory Balancing Accounts, Other balancing accounts [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	85	(58)
Southern California Gas Company [Member] | Other regulatory assets [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	160	75
Southern California Gas Company [Member] | Net Regulatory Assets (Liabilities) SoCalGas [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(43)	(32)
Sempra Mexico [Member] | Deferred income taxes (refundable) recoverable in rates [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	$ 80	$ 80