REGULATORY MATTERS - COST OF CAPITAL & FERC RATES (Details) - USD ($) $ in Millions	1 Months Ended		12 Months Ended		36 Months Ended
	Jan. 31, 2020	Oct. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2022
San Diego Gas and Electric Company [Member]
Public Utilities, General Disclosures [Line Items]
Minimum common equity ratio (as a percent)		10.60%
FERC requirement to maintain common equity ratio at or above, base (as a percent)		10.10%
FERC requirement, additional basis spread		0.50%
FERC, revenue requirement			$ 12
San Diego Gas and Electric Company [Member] | California Public Utilities Commission [Member]
Public Utilities, General Disclosures [Line Items]
CCM benchmark rate (as a percent)			4.498%
San Diego Gas and Electric Company [Member] | Federal Energy Regulatory Commission [Member]
Public Utilities, General Disclosures [Line Items]
FERC requirement, additional basis spread		0.50%
FERC, revenue requirement			$ 17
San Diego Gas and Electric Company [Member] | Capital Structure, Preferred Stock [Member] | California Public Utilities Commission [Member]
Public Utilities, General Disclosures [Line Items]
Authorized weighting	6.22%
San Diego Gas and Electric Company [Member] | Capital Structure, Common Equity [Member] | Federal Energy Regulatory Commission [Member]
Public Utilities, General Disclosures [Line Items]
Return on rate base (as a percent)				10.05%
Southern California Gas Company [Member] | California Public Utilities Commission [Member]
Public Utilities, General Disclosures [Line Items]
CCM benchmark rate (as a percent)			4.029%
Forecast [Member] | San Diego Gas and Electric Company [Member] | California Public Utilities Commission [Member]
Public Utilities, General Disclosures [Line Items]
Authorized weighting					100.00%
Weighted return on rate base					7.55%
Forecast [Member] | San Diego Gas and Electric Company [Member] | authorized weighting | California Public Utilities Commission [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Debt Capital Structure, Percentage					45.25%
Forecast [Member] | San Diego Gas and Electric Company [Member] | authorized weighting | California Public Utilities Commission [Member] | Preferred Equity
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Return on Equity, Percentage					2.75%
Forecast [Member] | San Diego Gas and Electric Company [Member] | authorized weighting | California Public Utilities Commission [Member] | Capital Structure, Common Equity [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Return on Equity, Percentage					52.00%
Forecast [Member] | San Diego Gas and Electric Company [Member] | Return on Rate Base | California Public Utilities Commission [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Debt Capital Structure, Percentage					4.59%
Forecast [Member] | San Diego Gas and Electric Company [Member] | Return on Rate Base | California Public Utilities Commission [Member] | Preferred Equity
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Return on Equity, Percentage					6.22%
Forecast [Member] | San Diego Gas and Electric Company [Member] | Return on Rate Base | California Public Utilities Commission [Member] | Capital Structure, Common Equity [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Return on Equity, Percentage					10.20%
Forecast [Member] | San Diego Gas and Electric Company [Member] | Weighted Return on Rate Base | California Public Utilities Commission [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Debt Capital Structure, Percentage					2.08%
Forecast [Member] | San Diego Gas and Electric Company [Member] | Weighted Return on Rate Base | California Public Utilities Commission [Member] | Preferred Equity
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Return on Equity, Percentage					0.17%
Forecast [Member] | San Diego Gas and Electric Company [Member] | Weighted Return on Rate Base | California Public Utilities Commission [Member] | Capital Structure, Common Equity [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Return on Equity, Percentage					5.30%
Forecast [Member] | Southern California Gas Company [Member] | California Public Utilities Commission [Member]
Public Utilities, General Disclosures [Line Items]
Authorized weighting					100.00%
Weighted return on rate base					7.30%
Forecast [Member] | Southern California Gas Company [Member] | authorized weighting | California Public Utilities Commission [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Debt Capital Structure, Percentage					45.60%
Forecast [Member] | Southern California Gas Company [Member] | authorized weighting | California Public Utilities Commission [Member] | Preferred Equity
Public Utilities, General Disclosures [Line Items]
Return on rate base (as a percent)					2.40%
Forecast [Member] | Southern California Gas Company [Member] | authorized weighting | California Public Utilities Commission [Member] | Capital Structure, Common Equity [Member]
Public Utilities, General Disclosures [Line Items]
Return on rate base (as a percent)					52.00%
Forecast [Member] | Southern California Gas Company [Member] | Return on Rate Base | California Public Utilities Commission [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Debt Capital Structure, Percentage					4.23%
Forecast [Member] | Southern California Gas Company [Member] | Return on Rate Base | California Public Utilities Commission [Member] | Preferred Equity
Public Utilities, General Disclosures [Line Items]
Return on rate base (as a percent)					6.00%
Forecast [Member] | Southern California Gas Company [Member] | Return on Rate Base | California Public Utilities Commission [Member] | Capital Structure, Common Equity [Member]
Public Utilities, General Disclosures [Line Items]
Return on rate base (as a percent)					10.05%
Forecast [Member] | Southern California Gas Company [Member] | Weighted Return on Rate Base | California Public Utilities Commission [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Debt Capital Structure, Percentage					1.93%
Forecast [Member] | Southern California Gas Company [Member] | Weighted Return on Rate Base | California Public Utilities Commission [Member] | Preferred Equity
Public Utilities, General Disclosures [Line Items]
Return on rate base (as a percent)					0.14%
Forecast [Member] | Southern California Gas Company [Member] | Weighted Return on Rate Base | California Public Utilities Commission [Member] | Capital Structure, Common Equity [Member]
Public Utilities, General Disclosures [Line Items]
Return on rate base (as a percent)					5.23%