SEGMENT INFORMATION (Details) $ in Millions	3 Months Ended									12 Months Ended
	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)		Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) segment	Dec. 31, 2016 USD ($)		Dec. 31, 2015 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments | segment										6
Segment Reporting Information, Profit (Loss) [Abstract]
Segment reporting information, Revenue										$ 11,207	$ 10,183		$ 10,231
Segment reporting information, Interest Expense										659	553		561
Segment reporting information, Interest Income										46	26		29
Segment reporting information, Depreciation and Amortization										1,490	1,312		1,250
Segment reporting information, Income Tax Expense (Benefit)										1,276	389		341
Earnings attributable to common shares	$ (501)	$ 57	$ 259	$ 441	$ 379		$ 622	$ 16	$ 353	256	1,370		1,349
Segment Reporting Information, Additional Information [Abstract]
Segment reporting information, Assets	50,454				47,786	[1]				50,454	47,786	[1]	41,150
Segment Reporting Information Expenditures For Property Plant and Equipment										3,949	4,214		3,156
Assets, geographical	39,030				35,028					39,030	35,028		30,944
Entity-Wide Disclosure On Geographic Areas, United States [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Segment reporting information, Revenue										8,547	8,004		8,119
Segment Reporting Information, Additional Information [Abstract]
Assets, geographical	31,487				28,351					31,487	28,351		26,132
Entity-Wide Disclosure On Geographic Areas, South America [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Segment reporting information, Revenue										1,567	1,556		1,544
Segment Reporting Information, Additional Information [Abstract]
Assets, geographical	2,180				1,863					2,180	1,863		1,652
Entity-Wide Disclosure On Geographic Areas Mexico [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Segment reporting information, Revenue										1,093	623		568
Segment Reporting Information, Additional Information [Abstract]
Assets, geographical	5,363				4,814					5,363	4,814		3,160
Operating Segments [Member] | SDG&E [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Segment reporting information, Revenue										4,476	4,253		4,219
Segment reporting information, Interest Expense										203	195		204
Segment reporting information, Depreciation and Amortization										670	646		604
Segment reporting information, Income Tax Expense (Benefit)										155	280		284
Earnings attributable to common shares										407	570		587
Segment Reporting Information, Additional Information [Abstract]
Segment reporting information, Assets	17,844				17,719					17,844	17,719		16,515
Segment Reporting Information Expenditures For Property Plant and Equipment										1,555	1,399		1,133
Operating Segments [Member] | SoCalGas [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Segment reporting information, Revenue										3,785	3,471		3,489
Segment reporting information, Interest Expense										102	97		84
Segment reporting information, Interest Income										1	1		4
Segment reporting information, Depreciation and Amortization										515	476		461
Segment reporting information, Income Tax Expense (Benefit)										160	143		138
Earnings attributable to common shares										396	349		419
Segment Reporting Information, Additional Information [Abstract]
Segment reporting information, Assets	14,159				13,424					14,159	13,424		12,104
Segment Reporting Information Expenditures For Property Plant and Equipment										1,367	1,319		1,352
Operating Segments [Member] | Sempra South American Utilities [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Segment reporting information, Revenue										1,567	1,556		1,544
Segment reporting information, Interest Expense										38	38		32
Segment reporting information, Interest Income										28	21		19
Segment reporting information, Depreciation and Amortization										54	49		50
Segment reporting information, Income Tax Expense (Benefit)										80	80		67
Earnings attributable to common shares										186	156		175
Segment Reporting Information, Additional Information [Abstract]
Segment reporting information, Assets	4,060				3,591					4,060	3,591		3,235
Segment Reporting Information Expenditures For Property Plant and Equipment										244	194		154
Operating Segments [Member] | Sempra Mexico [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Segment reporting information, Revenue										1,196	725		669
Segment reporting information, Interest Expense										97	13		23
Segment reporting information, Interest Income										23	6		7
Segment reporting information, Depreciation and Amortization										156	77		70
Segment reporting information, Income Tax Expense (Benefit)										227	188		11
Earnings attributable to common shares										169	463		213
Segment Reporting Information, Additional Information [Abstract]
Segment reporting information, Assets	8,554				7,542					8,554	7,542		3,783
Segment Reporting Information Expenditures For Property Plant and Equipment										248	330		302
Operating Segments [Member] | Sempra Renewables [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Segment reporting information, Revenue										94	34		36
Segment reporting information, Interest Expense										15	4		3
Segment reporting information, Interest Income										7	5		4
Segment reporting information, Depreciation and Amortization										38	6		6
Segment reporting information, Income Tax Expense (Benefit)										(226)	(38)		(49)
Earnings attributable to common shares										252	55		63
Segment Reporting Information, Additional Information [Abstract]
Segment reporting information, Assets	2,898				3,644					2,898	3,644		1,441
Segment Reporting Information Expenditures For Property Plant and Equipment										497	835		81
Operating Segments [Member] | Sempra LNG & Midstream [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Segment reporting information, Revenue										540	508		653
Segment reporting information, Interest Expense										39	43		72
Segment reporting information, Interest Income										56	71		75
Segment reporting information, Depreciation and Amortization										42	47		49
Segment reporting information, Income Tax Expense (Benefit)										(119)	(80)		28
Earnings attributable to common shares										150	(107)		44
Segment Reporting Information, Additional Information [Abstract]
Segment reporting information, Assets	4,872				5,564					4,872	5,564		5,566
Segment Reporting Information Expenditures For Property Plant and Equipment										20	117		87
Adjustment and Elimination [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Segment reporting information, Revenue										(1)	0		(2)
All Other [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Segment reporting information, Interest Expense										284	282		263
Segment reporting information, Depreciation and Amortization										15	11		10
Segment reporting information, Income Tax Expense (Benefit)										999	(184)		(138)
Earnings attributable to common shares										(1,304)	(116)		(152)
Segment Reporting Information, Additional Information [Abstract]
Segment reporting information, Assets	915				475					915	475		734
Segment Reporting Information Expenditures For Property Plant and Equipment										18	20		47
Intersegment Eliminations [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Segment reporting information, Revenue										(450)	(364)		(377)
Segment reporting information, Interest Expense										(119)	(119)		(120)
Segment reporting information, Interest Income										(69)	(78)		(80)
Segment Reporting Information, Additional Information [Abstract]
Segment reporting information, Assets	$ (2,848)				$ (4,173)					(2,848)	(4,173)		(2,228)
Intersegment Eliminations [Member] | SDG&E [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Segment reporting information, Revenue										7	6		9
Intersegment Eliminations [Member] | SoCalGas [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Segment reporting information, Revenue										74	76		75
Intersegment Eliminations [Member] | Sempra Mexico [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Segment reporting information, Revenue										103	102		101
Intersegment Eliminations [Member] | Sempra LNG & Midstream [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Segment reporting information, Revenue										$ 266	$ 180		$ 192

[1] Reflects reclassifications to conform to current year presentation, which we discuss in Note 1.