FAIR VALUE MEASUREMENTS - FINANCIAL INSTRUMENTS (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Allowance for credit losses	$ 6	$ 7
Unamortized transaction costs	4	5
Unamortized discount and debt issuance costs	326	289
Finance lease obligations	1,346	1,343
Carrying amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term notes receivable	330	318
Long-term amounts due to unconsolidated affiliates	308	301
Total long-term debt	27,657	24,513
Fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term notes receivable	295	286
Long-term amounts due to unconsolidated affiliates	269	263
Total long-term debt	23,765	21,549
Fair value | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term notes receivable	0	0
Long-term amounts due to unconsolidated affiliates	0	0
Total long-term debt	0	0
Fair value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term notes receivable	0	0
Long-term amounts due to unconsolidated affiliates	269	263
Total long-term debt	23,765	21,549
Fair value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term notes receivable	295	286
Long-term amounts due to unconsolidated affiliates	0	0
Total long-term debt	0	0
San Diego Gas and Electric Company
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized discount and debt issuance costs	90	70
Finance lease obligations	1,234	1,256
San Diego Gas and Electric Company | Carrying amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total long-term debt	8,750	7,800
San Diego Gas and Electric Company | Fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total long-term debt	7,202	6,726
San Diego Gas and Electric Company | Fair value | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total long-term debt	0	0
San Diego Gas and Electric Company | Fair value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total long-term debt	7,202	6,726
San Diego Gas and Electric Company | Fair value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total long-term debt	0	0
Southern California Gas Company
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized discount and debt issuance costs	57	48
Finance lease obligations	112	87
Southern California Gas Company | Carrying amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total long-term debt	6,759	6,059
Southern California Gas Company | Fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total long-term debt	5,953	5,538
Southern California Gas Company | Fair value | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total long-term debt	0	0
Southern California Gas Company | Fair value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total long-term debt	5,953	5,538
Southern California Gas Company | Fair value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total long-term debt	$ 0	$ 0