DERIVATIVE FINANCIAL INSTRUMENTS - DERIVATIVE IMPACT ON INCOME (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Derivative [Line Items]
Pretax (loss) gain on derivatives recognized in earnings	$ 7	$ 5	$ (23)	$ (148)
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member]
Derivative [Line Items]
Pretax (loss) gain recognized in OCI	(33)	(18)	76	(261)
Pretax gain (loss) reclassified from AOCI into earnings	(11)	0	(40)	(39)
Designated as Hedging Instrument [Member] | Interest Expense [Member] | Cash Flow Hedging [Member] | Interest Rate Contract [Member]
Derivative [Line Items]
Pretax (loss) gain recognized in OCI	(6)	(3)	20	(50)
Pretax gain (loss) reclassified from AOCI into earnings	1	(1)	(1)	(3)
Designated as Hedging Instrument [Member] | Interest Expense [Member] | Cash Flow Hedging [Member] | Interest rate and foreign exchange instruments [Member]
Derivative [Line Items]
Pretax (loss) gain recognized in OCI	7	8	1	(37)
Pretax gain (loss) reclassified from AOCI into earnings	0	(1)	0	(1)
Designated as Hedging Instrument [Member] | Equity Earnings [Member] | Cash Flow Hedging [Member] | Interest Rate Contract [Member]
Derivative [Line Items]
Pretax (loss) gain recognized in OCI	(32)	(15)	51	(200)
Pretax gain (loss) reclassified from AOCI into earnings	(19)	(1)	(38)	(3)
Designated as Hedging Instrument [Member] | Equity Earnings [Member] | Cash Flow Hedging [Member] | Foreign Exchange Instruments [Member]
Derivative [Line Items]
Pretax (loss) gain recognized in OCI	(1)	(3)	2	10
Pretax gain (loss) reclassified from AOCI into earnings	0	0	(1)	2
Designated as Hedging Instrument [Member] | Revenues: Energy-Related Businesses [Member] | Cash Flow Hedging [Member] | Foreign Exchange Instruments [Member]
Derivative [Line Items]
Pretax (loss) gain recognized in OCI	(1)	(5)	2	16
Pretax gain (loss) reclassified from AOCI into earnings	0	0	(1)	2
Designated as Hedging Instrument [Member] | Other Income (Expense), Net [Member] | Cash Flow Hedging [Member] | Foreign Exchange Instruments [Member]
Derivative [Line Items]
Pretax gain (loss) reclassified from AOCI into earnings	0	(1)	0	1
Designated as Hedging Instrument [Member] | Other Income (Expense), Net [Member] | Cash Flow Hedging [Member] | Interest rate and foreign exchange instruments [Member]
Derivative [Line Items]
Pretax gain (loss) reclassified from AOCI into earnings	7	4	1	(37)
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Pretax (loss) gain on derivatives recognized in earnings	(101)	21	(169)	(54)
Not Designated as Hedging Instrument [Member] | Revenues: Energy-Related Businesses [Member] | Commodity Contracts not subject to rate recovery [Member]
Derivative [Line Items]
Pretax (loss) gain on derivatives recognized in earnings	(142)	13	(190)	64
Not Designated as Hedging Instrument [Member] | Other Income (Expense), Net [Member] | Foreign Exchange Instruments [Member]
Derivative [Line Items]
Pretax (loss) gain on derivatives recognized in earnings	0	2	(24)	(112)
Not Designated as Hedging Instrument [Member] | Cost of Electric Fuel and Purchased Power [Member] | Commodity Contracts Subject To Rate Recovery [Member]
Derivative [Line Items]
Pretax (loss) gain on derivatives recognized in earnings	41	9	43	0
Not Designated as Hedging Instrument [Member] | Cost of Natural Gas [Member] | Commodity Contracts Subject To Rate Recovery [Member]
Derivative [Line Items]
Pretax (loss) gain on derivatives recognized in earnings	0	(3)	2	(6)
San Diego Gas and Electric Company [Member] | Not Designated as Hedging Instrument [Member] | Cost of Electric Fuel and Purchased Power [Member] | Commodity Contracts Subject To Rate Recovery [Member]
Derivative [Line Items]
Pretax (loss) gain on derivatives recognized in earnings	41	9	43	0
Southern California Gas Company [Member] | Not Designated as Hedging Instrument [Member] | Cost of Natural Gas [Member] | Commodity Contracts Subject To Rate Recovery [Member]
Derivative [Line Items]
Pretax (loss) gain on derivatives recognized in earnings	$ 0	$ (3)	$ 2	$ (6)