REGULATORY MATTERS - REGULATORY ACCOUNTS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Amortization of Regulatory Asset	$ 9	$ 7	$ 5
Net Regulatory Assets (Liabilities) Sempra Energy Consolidated [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(1,500)	(1,908)
San Diego Gas and Electric Company [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Regulatory balancing accounts - net undercollected, Noncurrent	139	108
Amortization of Regulatory Asset	4	3	2
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)	(53)	8
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)	22	(108)
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)	50	103
San Diego Gas and Electric Company [Member] | Removal obligations [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(2,121)	(2,056)
San Diego Gas and Electric Company [Member] | Environmental costs [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	56	45
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
Regulatory Asset, Amortization Period	49 years
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)	$ 72	102
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)	35	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)	67	77
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)	(158)	(124)
San Diego Gas and Electric Company [Member] | GRC retroactive impacts [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	56	111
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)	233	106
San Diego Gas and Electric Company [Member] | Other regulatory (liabilities) assets [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	72	(153)
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)	(1,548)	(1,746)
Southern California Gas Company [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Regulatory balancing accounts - net undercollected, Noncurrent	218	500
Amortization of Regulatory Asset	5	4	$ 3
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)	(82)	(203)
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)	417	400
Southern California Gas Company [Member] | Employee benefit costs [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	37	44
Southern California Gas Company [Member] | Removal obligations [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(685)	(728)
Southern California Gas Company [Member] | Environmental costs [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	36	40
Southern California Gas Company [Member] | Regulatory Balancing Accounts, Safety and reliability [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	335	295
Southern California Gas Company [Member] | Regulatory Balancing Accounts, Public purpose programs [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(253)	(273)
Southern California Gas Company [Member] | Regulatory Balancing Accounts, Commodity - gas including transportation
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(56)	(118)
Southern California Gas Company [Member] | GRC retroactive impacts [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	202	400
Southern California Gas Company [Member] | Regulatory Balancing Accounts, Other balancing accounts [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(58)	(7)
Southern California Gas Company [Member] | Other regulatory (liabilities) assets [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	75	(101)
Southern California Gas Company [Member] | Net Regulatory Assets (Liabilities) SoCalGas [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	(32)	(251)
Sempra Mexico [Member] | Deferred income taxes (refundable) recoverable in rates [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	80	83
Sempra Mexico [Member] | Other Regulatory Assets [Member]
Schedule Of Net Regulatory Assets (Liabilities) [Line Items]
Net regulatory assets (liabilities)	$ 0	$ 6