REGULATORY MATTERS - GENERAL RATE CASE (Details) - USD ($) $ in Millions		1 Months Ended	6 Months Ended
	Oct. 06, 2017	Apr. 30, 2018	Jun. 30, 2019
San Diego Gas and Electric Company [Member]
General Rate Case [Line Items]
GRC requested revenue requirement	$ 2,203	$ 1,918
GRC requested revenue requirement adjustment	221	$ 64
Tax Cuts and Jobs Act, change in tax rate, change in revenue requirement			$ 58
Proposed annual attrition percentage		4.00%
San Diego Gas and Electric Company [Member] | General Rate Case [Member]
General Rate Case [Line Items]
Tracked income tax expense liability			93
San Diego Gas and Electric Company [Member] | Future Refund of Rates to Customers [Member]
General Rate Case [Line Items]
Regulatory liability			113
San Diego Gas and Electric Company [Member] | Future Refund of Rates to Customers - FERC [Member]
General Rate Case [Line Items]
Regulatory liability			93
Southern California Gas Company [Member]
General Rate Case [Line Items]
GRC requested revenue requirement	2,937	$ 2,695
GRC requested revenue requirement adjustment	$ 481	$ 239
Tax Cuts and Jobs Act, change in tax rate, change in revenue requirement			58
Southern California Gas Company [Member] | General Rate Case [Member]
General Rate Case [Line Items]
Tracked income tax expense liability			100
Southern California Gas Company [Member] | Future Refund of Rates to Customers [Member]
General Rate Case [Line Items]
Regulatory liability			$ 106
Minimum [Member] | San Diego Gas and Electric Company [Member]
General Rate Case [Line Items]
GRC requested revenue requirement adjustment percentage	5.00%
Minimum [Member] | Southern California Gas Company [Member]
General Rate Case [Line Items]
GRC requested revenue requirement adjustment percentage	6.00%
Proposed annual attrition percentage		4.00%
Maximum [Member] | San Diego Gas and Electric Company [Member]
General Rate Case [Line Items]
GRC requested revenue requirement adjustment percentage	7.00%
Maximum [Member] | Southern California Gas Company [Member]
General Rate Case [Line Items]
GRC requested revenue requirement adjustment percentage	8.00%
Proposed annual attrition percentage		5.00%
Otay Mesa Energy Center [Member] | San Diego Gas and Electric Company [Member]
General Rate Case [Line Items]
Owning and operating costs		$ 68