REVENUES - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	[1]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	$ 2,896
Utilities regulatory revenues	(31)
Other revenues	97
Total revenues	2,962	$ 3,031
Over time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2,823
Point in time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	73
Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2,629
Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	176
Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	33
Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	58
Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,459
Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,437
Operating Segments [Member] | San Diego Gas and Electric Company [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,131
Utilities regulatory revenues	(76)
Other revenues	0
Total revenues	1,055
Operating Segments [Member] | San Diego Gas and Electric Company [Member] | Over time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,104
Operating Segments [Member] | San Diego Gas and Electric Company [Member] | Point in time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	27
Operating Segments [Member] | San Diego Gas and Electric Company [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,131
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
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
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
Operating Segments [Member] | San Diego Gas and Electric Company [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	963
Operating Segments [Member] | San Diego Gas and Electric Company [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	168
Operating Segments [Member] | Southern California Gas Company [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,081
Utilities regulatory revenues	45
Other revenues	0
Total revenues	1,126
Operating Segments [Member] | Southern California Gas Company [Member] | Over time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,051
Operating Segments [Member] | Southern California Gas Company [Member] | Point in time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	30
Operating Segments [Member] | Southern California Gas Company [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,081
Operating Segments [Member] | Southern California Gas Company [Member] | Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Operating Segments [Member] | Southern California Gas Company [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Operating Segments [Member] | Southern California Gas Company [Member] | Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Operating Segments [Member] | Southern California Gas Company [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Operating Segments [Member] | Southern California Gas Company [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,081
Operating Segments [Member] | Sempra South American Utilities [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	425
Utilities regulatory revenues	0
Other revenues	1
Total revenues	426
Operating Segments [Member] | Sempra South American Utilities [Member] | Over time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	420
Operating Segments [Member] | Sempra South American Utilities [Member] | Point in time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	5
Operating Segments [Member] | Sempra South American Utilities [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	408
Operating Segments [Member] | Sempra South American Utilities [Member] | Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Operating Segments [Member] | Sempra South American Utilities [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Operating Segments [Member] | Sempra South American Utilities [Member] | Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	17
Operating Segments [Member] | Sempra South American Utilities [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	425
Operating Segments [Member] | Sempra South American Utilities [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Operating Segments [Member] | Sempra Mexico [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	234
Utilities regulatory revenues	0
Other revenues	74
Total revenues	308
Operating Segments [Member] | Sempra Mexico [Member] | Over time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	234
Operating Segments [Member] | Sempra Mexico [Member] | Point in time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Operating Segments [Member] | Sempra Mexico [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	28
Operating Segments [Member] | Sempra Mexico [Member] | Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	143
Operating Segments [Member] | Sempra Mexico [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	22
Operating Segments [Member] | Sempra Mexico [Member] | Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	41
Operating Segments [Member] | Sempra Mexico [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	62
Operating Segments [Member] | Sempra Mexico [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	172
Operating Segments [Member] | Sempra Renewables [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	11
Utilities regulatory revenues	0
Other revenues	14
Total revenues	25
Operating Segments [Member] | Sempra Renewables [Member] | Over time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	11
Operating Segments [Member] | Sempra Renewables [Member] | Point in time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Operating Segments [Member] | Sempra Renewables [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Operating Segments [Member] | Sempra Renewables [Member] | Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Operating Segments [Member] | Sempra Renewables [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	11
Operating Segments [Member] | Sempra Renewables [Member] | Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Operating Segments [Member] | Sempra Renewables [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	11
Operating Segments [Member] | Sempra Renewables [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Operating Segments [Member] | Sempra LNG & Midstream [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	57
Utilities regulatory revenues	0
Other revenues	47
Total revenues	104
Operating Segments [Member] | Sempra LNG & Midstream [Member] | Over time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	40
Operating Segments [Member] | Sempra LNG & Midstream [Member] | Point in time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	17
Operating Segments [Member] | Sempra LNG & Midstream [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Operating Segments [Member] | Sempra LNG & Midstream [Member] | Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	54
Operating Segments [Member] | Sempra LNG & Midstream [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1
Operating Segments [Member] | Sempra LNG & Midstream [Member] | Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2
Operating Segments [Member] | Sempra LNG & Midstream [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2
Operating Segments [Member] | Sempra LNG & Midstream [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	55
Consolidating Adjustments [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(43)
Utilities regulatory revenues	0
Other revenues	(39)
Total revenues	(82)
Consolidating Adjustments [Member] | Over time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(37)
Consolidating Adjustments [Member] | Point in time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(6)
Consolidating Adjustments [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(19)
Consolidating Adjustments [Member] | Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(21)
Consolidating Adjustments [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(1)
Consolidating Adjustments [Member] | Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(2)
Consolidating Adjustments [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(4)
Consolidating Adjustments [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	$ (39)

[1] As adjusted for the retrospective adoption of ASU 2017-07, which we discuss in Note 2, and a reclassification to conform to current year presentation, which we discuss in Note 1.