GENERAL INFORMATION AND OTHER FINANCIAL DATA - INCOME TAXES (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Tax Expense And Effective Income Tax Rates Disclosure [Line Items]
Income tax (benefit) expense from continuing operations	$ (207)	$ 42
Income (loss) from continuing operations before income taxes and equity earnings	397	501
Equity earnings (losses), before income tax	(43)	5
Pretax income	$ 354	$ 506
Effective income tax rate	(58.00%)	8.00%
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)	13
San Diego Gas and Electric Company [Member]
Income Tax Expense And Effective Income Tax Rates Disclosure [Line Items]
Income tax (benefit) expense from continuing operations	58	5
Income (loss) from continuing operations before income taxes and equity earnings	$ 320	$ 182
Effective income tax rate	18.00%	3.00%
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 (benefit) expense from continuing operations	52	$ 19
Income (loss) from continuing operations before income taxes and equity earnings	$ 355	$ 283
Effective income tax rate	15.00%	7.00%
Income tax benefit for release of a regulatory liability	$ 35