REVENUES - DISAGGREGATION OF REVENUE (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	[1]	Jun. 30, 2018	Jun. 30, 2017	[1]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	$ 2,356			$ 5,252
Utilities regulatory revenues	95			64
Other revenues	113			210
Total revenues	2,564	$ 2,533		5,526	$ 5,564
Over time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2,294			5,117
Point in time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	62			135
Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2,095			4,724
Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	169			345
Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	44			77
Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	48			106
Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,349			2,808
Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,007			2,444
Operating Segments [Member] | San Diego Gas and Electric Company [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	999			2,130
Utilities regulatory revenues	52			(24)
Other revenues	0			0
Total revenues	1,051			2,106
Operating Segments [Member] | San Diego Gas and Electric Company [Member] | Over time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	972			2,076
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			54
Operating Segments [Member] | San Diego Gas and Electric Company [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	999			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
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
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
Operating Segments [Member] | San Diego Gas and Electric Company [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	886			1,849
Operating Segments [Member] | San Diego Gas and Electric Company [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	113			281
Operating Segments [Member] | Southern California Gas Company [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	729			1,810
Utilities regulatory revenues	43			88
Other revenues	0			0
Total revenues	772			1,898
Operating Segments [Member] | Southern California Gas Company [Member] | Over time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	699			1,750
Operating Segments [Member] | Southern California Gas Company [Member] | Point in time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	30			60
Operating Segments [Member] | Southern California Gas Company [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	729			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
Operating Segments [Member] | Southern California Gas Company [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	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
Operating Segments [Member] | Southern California Gas Company [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0			0
Operating Segments [Member] | Southern California Gas Company [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	729			1,810
Operating Segments [Member] | Sempra South American Utilities [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	387			812
Utilities regulatory revenues	0			0
Other revenues	2			3
Total revenues	389			815
Operating Segments [Member] | Sempra South American Utilities [Member] | Over time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	383			803
Operating Segments [Member] | Sempra South American Utilities [Member] | Point in time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	4			9
Operating Segments [Member] | Sempra South American Utilities [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	370			778
Operating Segments [Member] | Sempra South American Utilities [Member] | Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0			0
Operating Segments [Member] | Sempra South American Utilities [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0			0
Operating Segments [Member] | Sempra South American Utilities [Member] | Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	17			34
Operating Segments [Member] | Sempra South American Utilities [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	387			812
Operating Segments [Member] | Sempra South American Utilities [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0			0
Operating Segments [Member] | Sempra Mexico [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	221			455
Utilities regulatory revenues	0			0
Other revenues	89			163
Total revenues	310			618
Operating Segments [Member] | Sempra Mexico [Member] | Over time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	221			455
Operating Segments [Member] | Sempra Mexico [Member] | Point in time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0			0
Operating Segments [Member] | Sempra Mexico [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	13			41
Operating Segments [Member] | Sempra Mexico [Member] | Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	147			290
Operating Segments [Member] | Sempra Mexico [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	31			53
Operating Segments [Member] | Sempra Mexico [Member] | Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	30			71
Operating Segments [Member] | Sempra Mexico [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	62			124
Operating Segments [Member] | Sempra Mexico [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	159			331
Operating Segments [Member] | Sempra Renewables [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	12			23
Utilities regulatory revenues	0			0
Other revenues	28			42
Total revenues	40			65
Operating Segments [Member] | Sempra Renewables [Member] | Over time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	12			23
Operating Segments [Member] | Sempra Renewables [Member] | Point in time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0			0
Operating Segments [Member] | Sempra Renewables [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0			0
Operating Segments [Member] | Sempra Renewables [Member] | Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0			0
Operating Segments [Member] | Sempra Renewables [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	12			23
Operating Segments [Member] | Sempra Renewables [Member] | Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0			0
Operating Segments [Member] | Sempra Renewables [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	12			23
Operating Segments [Member] | Sempra Renewables [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0			0
Operating Segments [Member] | Sempra LNG & Midstream [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	37			94
Utilities regulatory revenues	0			0
Other revenues	42			89
Total revenues	79			183
Operating Segments [Member] | Sempra LNG & Midstream [Member] | Over time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	32			72
Operating Segments [Member] | Sempra LNG & Midstream [Member] | Point in time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	5			22
Operating Segments [Member] | Sempra LNG & Midstream [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0			0
Operating Segments [Member] | Sempra LNG & Midstream [Member] | Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	35			89
Operating Segments [Member] | Sempra LNG & Midstream [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0			1
Operating Segments [Member] | Sempra LNG & Midstream [Member] | Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2			4
Operating Segments [Member] | Sempra LNG & Midstream [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	3			5
Operating Segments [Member] | Sempra LNG & Midstream [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	34			89
Consolidating Adjustments [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(29)			(72)
Utilities regulatory revenues	0			0
Other revenues	(48)			(87)
Total revenues	(77)			(159)
Consolidating Adjustments [Member] | Over time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(25)			(62)
Consolidating Adjustments [Member] | Point in time [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(4)			(10)
Consolidating Adjustments [Member] | Utilities service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(16)			(35)
Consolidating Adjustments [Member] | Midstream service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(13)			(34)
Consolidating Adjustments [Member] | Renewables service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1			0
Consolidating Adjustments [Member] | Other service line [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(1)			(3)
Consolidating Adjustments [Member] | Electric market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	(1)			(5)
Consolidating Adjustments [Member] | Gas market [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	$ (28)			$ (67)

[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.