GENERAL INFORMATION AND OTHER FINANCIAL DATA - INCOME TAXES (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Tax Expense And Effective Income Tax Rates Disclosure [Line Items]
Income tax expense (benefit) from continuing operations	$ 168	$ 47	$ (39)	$ 89
Income from continuing operations before income taxes and equity earnings	463	286	860	787
Equity earnings (losses), before income tax	84	2	41	7
Pretax income	$ 547	$ 288	$ 901	$ 794
Effective income tax rate (as a percent)	31.00%	16.00%	(4.00%)	11.00%
Income tax expense (benefit) related to outside basis differences existing prior to the January 25, 2019 approval of our plan to sell our South American businesses				$ 103
Income tax expense related to the increase in outside basis differences from 2019 earnings since January 25, 2019			$ 7	20
San Diego Gas and Electric Company [Member]
Income Tax Expense And Effective Income Tax Rates Disclosure [Line Items]
Income tax expense (benefit) from continuing operations	$ 70	$ 35	128	40
Income from continuing operations before income taxes and equity earnings	$ 263	$ 181	$ 583	$ 363
Effective income tax rate (as a percent)	27.00%	19.00%	22.00%	11.00%
Income tax benefit for release of a regulatory liability			$ 31
Southern California Gas Company [Member]
Income Tax Expense And Effective Income Tax Rates Disclosure [Line Items]
Income tax expense (benefit) from continuing operations	$ 49	$ (4)	101	$ 15
Income from continuing operations before income taxes and equity earnings	$ 196	$ 27	$ 551	$ 310
Effective income tax rate (as a percent)	25.00%	(15.00%)	18.00%	5.00%
Income tax benefit for release of a regulatory liability			$ 38