GENERAL INFORMATION AND OTHER FINANCIAL DATA - INCOME TAXES (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Income Tax Expense And Effective Income Tax Rates Disclosure [Line Items]
Income tax expense	$ 334	$ 158
Income before income taxes and equity earnings	665	768
Equity earnings, before income tax:	143	135
Pretax income	$ 808	$ 903
Effective income tax rate (as a percent)	41.00%	18.00%
Deferred income tax liability for foreign earnings	$ 120
San Diego Gas and Electric Company
Income Tax Expense And Effective Income Tax Rates Disclosure [Line Items]
Income tax expense	64	$ 45
Income before income taxes and equity earnings	$ 298	$ 257
Effective income tax rate (as a percent)	21.00%	18.00%
Southern California Gas Company
Income Tax Expense And Effective Income Tax Rates Disclosure [Line Items]
Income tax expense	$ 84	$ 94
Income before income taxes and equity earnings	418	501
Pretax income	$ 418	$ 501
Effective income tax rate (as a percent)	20.00%	19.00%