SEGMENT INFORMATION (Details) $ in Millions	3 Months Ended	12 Months Ended			21 Months Ended
	Mar. 31, 2019 segment	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2020 USD ($) segment	May 16, 2019	Mar. 09, 2018
Segment Reporting Information [Line Items]
Number of reportable segments | segment	6				5
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUES		$ 11,370	$ 10,829	$ 10,102
INTEREST EXPENSE		1,081	1,077	886
INTEREST INCOME		96	87	85
DEPRECIATION AND AMORTIZATION		1,666	1,569	1,491
INCOME TAX EXPENSE (BENEFIT)		249	315	(49)
Earnings attributable to common shares		3,764	2,055	924
Income (loss) from discontinued operations, net of income tax		1,840	328	156
Segment Reporting Information, Additional Information [Abstract]
EXPENDITURES FOR PROPERTY, PLANT & EQUIPMENT		4,676	3,708	3,544
ASSETS		66,623	65,665	60,638	$ 66,623
Long-lived assets		53,831	50,074	46,411	53,831
Entity-Wide Disclosure On Geographic Areas, United States [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUES		10,205	9,574	8,840
Segment Reporting Information, Additional Information [Abstract]
Long-lived assets		46,902	43,719	40,611	46,902
Entity-Wide Disclosure On Geographic Areas Mexico [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUES		1,165	1,255	1,262
Segment Reporting Information, Additional Information [Abstract]
Long-lived assets		6,929	6,355	5,800	6,929
Operating Segments [Member] | SDG&E [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUES		5,313	4,925	4,568
INTEREST EXPENSE		413	411	221
INTEREST INCOME		2	4	4
DEPRECIATION AND AMORTIZATION		801	760	688
INCOME TAX EXPENSE (BENEFIT)		190	171	173
Earnings attributable to common shares		824	767	669
Segment Reporting Information, Additional Information [Abstract]
EXPENDITURES FOR PROPERTY, PLANT & EQUIPMENT		1,942	1,522	1,542
ASSETS		22,311	20,560	19,225	22,311
Operating Segments [Member] | SoCalGas [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUES		4,748	4,525	3,962
INTEREST EXPENSE		158	141	115
INTEREST INCOME		2	2	2
DEPRECIATION AND AMORTIZATION		654	602	556
INCOME TAX EXPENSE (BENEFIT)		96	120	92
Earnings attributable to common shares		504	641	400
Segment Reporting Information, Additional Information [Abstract]
EXPENDITURES FOR PROPERTY, PLANT & EQUIPMENT		1,843	1,439	1,538
ASSETS		18,460	17,077	15,389	18,460
Operating Segments [Member] | Sempra Texas Utilities [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
INCOME TAX EXPENSE (BENEFIT)		1	0	0
Earnings attributable to common shares		579	528	371
Segment Reporting Information, Additional Information [Abstract]
ASSETS		12,542	11,619	9,652	12,542
Operating Segments [Member] | Sempra Mexico [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUES		1,256	1,375	1,376
INTEREST EXPENSE		132	119	120
INTEREST INCOME		60	78	65
DEPRECIATION AND AMORTIZATION		189	183	175
INCOME TAX EXPENSE (BENEFIT)		57	227	185
Earnings attributable to common shares		259	253	237
Segment Reporting Information, Additional Information [Abstract]
EXPENDITURES FOR PROPERTY, PLANT & EQUIPMENT		611	624	368
ASSETS		10,752	9,938	9,165	10,752
Operating Segments [Member] | Sempra Renewables [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUES		0	10	124
INTEREST EXPENSE		0	3	19
INTEREST INCOME		0	11	12
DEPRECIATION AND AMORTIZATION		0	0	27
INCOME TAX EXPENSE (BENEFIT)		0	4	71
Earnings attributable to common shares		0	59	328
Segment Reporting Information, Additional Information [Abstract]
EXPENDITURES FOR PROPERTY, PLANT & EQUIPMENT		0	2	51
ASSETS		0	0	2,549	0
Operating Segments [Member] | Sempra LNG [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUES		374	410	472
INTEREST EXPENSE		43	35	21
INTEREST INCOME		81	61	49
DEPRECIATION AND AMORTIZATION		9	10	26
INCOME TAX EXPENSE (BENEFIT)		92	(5)	(435)
Earnings attributable to common shares		320	(6)	(617)
Segment Reporting Information, Additional Information [Abstract]
EXPENDITURES FOR PROPERTY, PLANT & EQUIPMENT		268	112	31
ASSETS		2,205	3,901	4,060	2,205
Adjustment and Elimination [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUES		(3)	(3)	(3)
Income (loss) from discontinued operations, net of income tax		1,840	328	156
Segment Reporting Information, Additional Information [Abstract]
Assets, discontinued operations		0	3,958	3,718	0
Intersegment Eliminations [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUES		(320)	(416)	(397)
INTEREST EXPENSE		(54)	(82)	(106)
INTEREST INCOME		(56)	(73)	(61)
Segment Reporting Information, Additional Information [Abstract]
ASSETS		(856)	(2,137)	(4,190)	(856)
Intersegment Eliminations [Member] | SDG&E [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUES		5	5	4
Intersegment Eliminations [Member] | SoCalGas [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUES		88	69	64
Intersegment Eliminations [Member] | Sempra Mexico [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUES		91	120	114
Intersegment Eliminations [Member] | Sempra LNG [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUES		136	222	215
All Other [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUES		2	3	0
INTEREST EXPENSE		389	450	496
INTEREST INCOME		7	4	14
DEPRECIATION AND AMORTIZATION		13	14	19
INCOME TAX EXPENSE (BENEFIT)		(187)	(202)	(135)
Earnings attributable to common shares		(562)	(515)	(620)
Segment Reporting Information, Additional Information [Abstract]
EXPENDITURES FOR PROPERTY, PLANT & EQUIPMENT		12	9	14
ASSETS		$ 1,209	$ 749	$ 1,070	$ 1,209
Oncor Electric Delivery Company LLC [Member]
Segment Reporting Information [Line Items]
Acquired percentage interest							80.25%
Oncor Electric Delivery Holdings Company LLC [Member] | Oncor Electric Delivery Company LLC [Member] | Sempra Texas Utilities [Member]
Segment Reporting Information [Line Items]
Ownership interest (as a percent)		80.25%			80.25%
Sharyland Holdings, LP [Member]
Segment Reporting Information [Line Items]
Acquired percentage interest						50.00%
Sharyland Holdings, LP [Member] | Sempra Texas Utilities [Member]
Segment Reporting Information [Line Items]
Acquired percentage interest						50.00%