REVENUES - PERFORMANCE OBLIGATIONS (Details) $ in Millions	Sep. 30, 2023 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 5,530
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 85
Revenues to be recognized, period of recognition	3 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 300
Revenues to be recognized, period of recognition	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 338
Revenues to be recognized, period of recognition	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 365
Revenues to be recognized, period of recognition	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 365
Revenues to be recognized, period of recognition	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 4,077
Revenues to be recognized, period of recognition
San Diego Gas and Electric Company
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 76
San Diego Gas and Electric Company | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 1
Revenues to be recognized, period of recognition	3 months
San Diego Gas and Electric Company | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 4
Revenues to be recognized, period of recognition	1 year
San Diego Gas and Electric Company | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 4
Revenues to be recognized, period of recognition	1 year
San Diego Gas and Electric Company | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 4
Revenues to be recognized, period of recognition	1 year
San Diego Gas and Electric Company | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 4
Revenues to be recognized, period of recognition	1 year
San Diego Gas and Electric Company | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 59
Revenues to be recognized, period of recognition