FAIR VALUE MEASUREMENTS - FINANCIAL INSTRUMENTS (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term amounts due from unconsolidated affiliates, allowance for credit losses		$ 1
Allowance for credit losses	$ 7	8
Unamortized transaction costs	5	5
Unamortized discount and debt issuance costs	294	260
Finance lease obligations	1,334	1,335
Due from Unconsolidated Affiliates - Current
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest Receivable	1	2
Carrying amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term and long-term amounts due from unconsolidated affiliates	626	640
Long-term notes receivable	310	300
Long-term amounts due to unconsolidated affiliate	282	287
Total long-term debt	23,924	20,099
Fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term and long-term amounts due from unconsolidated affiliates	630	642
Long-term notes receivable	278	327
Long-term amounts due to unconsolidated affiliate	251	295
Total long-term debt	21,709	22,126
Fair value | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term and long-term amounts due from unconsolidated affiliates	0	0
Long-term notes receivable	0	0
Long-term amounts due to unconsolidated affiliate	0	0
Total long-term debt	0	0
Fair value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term and long-term amounts due from unconsolidated affiliates	630	642
Long-term notes receivable	0	0
Long-term amounts due to unconsolidated affiliate	251	295
Total long-term debt	21,709	22,126
Fair value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term and long-term amounts due from unconsolidated affiliates	0	0
Long-term notes receivable	278	327
Long-term amounts due to unconsolidated affiliate	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	73	61
Finance lease obligations	1,266	1,274
San Diego Gas and Electric Company | Carrying amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total long-term debt	7,800	6,417
San Diego Gas and Electric Company | Fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total long-term debt	7,102	7,236
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	7,102	7,236
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	43	36
Finance lease obligations	68	61
Southern California Gas Company | Carrying amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total long-term debt	5,459	4,759
Southern California Gas Company | Fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total long-term debt	5,110	5,367
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	5,110	5,367
Southern California Gas Company | Fair value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total long-term debt	$ 0	$ 0