DERIVATIVE FINANCIAL INSTRUMENTS - COMMODITY VOLUMES (Details)	12 Months Ended
	Dec. 31, 2020 MWh MMBTU	Dec. 31, 2019 MMBTU MWh
Natural Gas Derivative [Member]
Derivatives, Fair Value [Line Items]
Notional amount, energy measure | MMBTU	5	32
Electric Energy Derivative [Member]
Derivatives, Fair Value [Line Items]
Notional amount, energy measure	1	2
Congestion Revenue Rights Derivative [Member]
Derivatives, Fair Value [Line Items]
Notional amount, energy measure	43	48
SDG&E [Member] | Natural Gas Derivative [Member]
Derivatives, Fair Value [Line Items]
Notional amount, energy measure | MMBTU	16	37
SDG&E [Member] | Electric Energy Derivative [Member]
Derivatives, Fair Value [Line Items]
Notional amount, energy measure	1	2
SDG&E [Member] | Congestion Revenue Rights Derivative [Member]
Derivatives, Fair Value [Line Items]
Notional amount, energy measure	43	48
SoCalGas [Member] | Natural Gas Derivative [Member]
Derivatives, Fair Value [Line Items]
Notional amount, energy measure | MMBTU	1	2