INVESTMENTS IN UNCONSOLIDATED ENTITIES - SUMMARIZED FINANCIAL INFORMATION (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Schedule of Equity Method Investments [Line Items]
Operating revenues	$ 2,845	$ 2,665
Other income (expense), net	35	(254)
Net income (loss)	928	947
Equity Method Investment, Nonconsolidated Investee or Group of Investees [Member] | Oncor Holdings [Member]
Schedule of Equity Method Investments [Line Items]
Operating revenues	1,139	1,072
Operating expenses	(829)	(801)
Operating income	310	271
Interest expense	(102)	(101)
Income tax expense	(36)	(28)
Net income (loss)	165	129
Noncontrolling interest held by TTI	(33)	(26)
Earnings attributable to Sempra Energy	132	103
Equity Method Investment, Nonconsolidated Investee or Group of Investees [Member] | IMG JV
Schedule of Equity Method Investments [Line Items]
Operating revenues	122	122
Operating expenses	(27)	(33)
Operating income	95	89
Other income (expense), net	58	364
Interest expense	(29)	(43)
Income tax expense	(31)	10
Net income (loss)	$ 93	$ 420