REVENUES - PERFORMANCE OBLIGATIONS (Details) $ in Millions	Mar. 31, 2022 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 6,021
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 277
Revenues to be recognized, period of recognition	9 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 367
Revenues to be recognized, period of recognition	1 year
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	$ 365
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	$ 362
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	$ 361
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	$ 4,289
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	$ 82
San Diego Gas and Electric Company | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues to be recognized	$ 3
Revenues to be recognized, period of recognition	9 months
San Diego Gas and Electric Company | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
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]: 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	$ 63
Revenues to be recognized, period of recognition