REVENUES - DISAGGREGATION OF REVENUE (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	$ 2,080	$ 1,969	$ 5,123	$ 4,440
Utilities regulatory revenues	25	95	(233)	64
Other revenues	125	111	238	207
Total revenues	2,230	2,175	5,128	4,711
Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,870	1,725	4,643	3,946
Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	151	169	330	345
Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	30	44	54	77
Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	29	31	96	72
Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,127	1,007	3,083	2,444
Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	953	962	2,040	1,996
Operating Segments [Member] | San Diego Gas and Electric Company [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	998	999	2,234	2,130
Utilities regulatory revenues	96	52	5	(24)
Other revenues	0	0	0	0
Total revenues	1,094	1,051	2,239	2,106
Operating Segments [Member] | San Diego Gas and Electric Company [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	998	999	2,234	2,130
Operating Segments [Member] | San Diego Gas and Electric Company [Member] | Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0	0	0
Operating Segments [Member] | San Diego Gas and Electric Company [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0	0	0
Operating Segments [Member] | San Diego Gas and Electric Company [Member] | Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0	0	0
Operating Segments [Member] | San Diego Gas and Electric Company [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	102	113	341	281
Operating Segments [Member] | San Diego Gas and Electric Company [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	896	886	1,893	1,849
Operating Segments [Member] | Southern California Gas Company [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	877	729	2,405	1,810
Utilities regulatory revenues	(71)	43	(238)	88
Other revenues	0	0	0	0
Total revenues	806	772	2,167	1,898
Operating Segments [Member] | Southern California Gas Company [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	877	729	2,405	1,810
Operating Segments [Member] | Southern California Gas Company [Member] | Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0	0	0
Operating Segments [Member] | Southern California Gas Company [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0	0	0
Operating Segments [Member] | Southern California Gas Company [Member] | Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0	0	0
Operating Segments [Member] | Southern California Gas Company [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	877	729	2,405	1,810
Operating Segments [Member] | Southern California Gas Company [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0	0	0
Operating Segments [Member] | Sempra Mexico [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	217	221	501	455
Utilities regulatory revenues	0	0	0	0
Other revenues	101	89	200	163
Total revenues	318	310	701	618
Operating Segments [Member] | Sempra Mexico [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	15	13	42	41
Operating Segments [Member] | Sempra Mexico [Member] | Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	143	147	314	290
Operating Segments [Member] | Sempra Mexico [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	30	31	50	53
Operating Segments [Member] | Sempra Mexico [Member] | Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	29	30	95	71
Operating Segments [Member] | Sempra Mexico [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	158	159	356	331
Operating Segments [Member] | Sempra Mexico [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	59	62	145	124
Operating Segments [Member] | Sempra Renewables [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1	12	5	23
Utilities regulatory revenues	0	0	0	0
Other revenues	2	28	5	42
Total revenues	3	40	10	65
Operating Segments [Member] | Sempra Renewables [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0	0	0
Operating Segments [Member] | Sempra Renewables [Member] | Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0	0	0
Operating Segments [Member] | Sempra Renewables [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1	12	5	23
Operating Segments [Member] | Sempra Renewables [Member] | Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0	0	0
Operating Segments [Member] | Sempra Renewables [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0	0	0
Operating Segments [Member] | Sempra Renewables [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1	12	5	23
Operating Segments [Member] | Sempra LNG [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	21	37	89	94
Utilities regulatory revenues	0	0	0	0
Other revenues	65	42	138	89
Total revenues	86	79	227	183
Operating Segments [Member] | Sempra LNG [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0	0	0
Operating Segments [Member] | Sempra LNG [Member] | Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	19	35	86	89
Operating Segments [Member] | Sempra LNG [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0	0	1
Operating Segments [Member] | Sempra LNG [Member] | Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2	2	3	4
Operating Segments [Member] | Sempra LNG [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	19	34	86	89
Operating Segments [Member] | Sempra LNG [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2	3	3	5
Consolidation, Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(34)	(29)	(111)	(72)
Utilities regulatory revenues	0	0	0	0
Other revenues	(43)	(48)	(105)	(87)
Total revenues	(77)	(77)	(216)	(159)
Consolidation, Eliminations [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(20)	(16)	(38)	(35)
Consolidation, Eliminations [Member] | Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(11)	(13)	(70)	(34)
Consolidation, Eliminations [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(1)	1	(1)	0
Consolidation, Eliminations [Member] | Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(2)	(1)	(2)	(3)
Consolidation, Eliminations [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(29)	(28)	(105)	(67)
Consolidation, Eliminations [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	$ (5)	$ (1)	$ (6)	$ (5)