GENERAL INFORMATION AND OTHER FINANCIAL DATA - VARIABLE INTEREST ENTITIES (Details) $ in Millions		3 Months Ended
	Mar. 09, 2018	Mar. 31, 2019 USD ($) MW	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)
Variable Interest Entities [Line Items]
Equity method investment		$ 9,748		$ 9,652	[1]
Energy-related businesses		383	$ 346
Operation and maintenance		(832)	(741)
Depreciation and amortization		(383)	(372)
Interest expense		(260)	(206)
Income from continuing operations before income taxes and equity earnings (losses) of unconsolidated entities		501	593
Income tax expense		(42)	(242)
Net income		518	358
(Earnings) losses attributable to noncontrolling interest		(41)	17
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entities [Line Items]
Assets of VIEs		502		286
Sempra Texas Utility [Member] | Oncor Holdings [Member]
Variable Interest Entities [Line Items]
Equity method investment		9,748		9,652
Commitment to invest		1,025
Management Agreement Termination Fee		40
Sempra Renewables [Member] | Tax Equity Investors [Member]
Variable Interest Entities [Line Items]
Equity		161		158
Energy-related businesses		6	17
Operation and maintenance		(2)	(4)
Depreciation and amortization		(3)	(11)
Income from continuing operations before income taxes and equity earnings (losses) of unconsolidated entities		1	2
Income tax expense		1	(5)
Net income		2	(3)
(Earnings) losses attributable to noncontrolling interest		(3)	21
Earnings attributable to common shares		(1)	18
Sempra Natural Gas [Member] | Cameron LNG Holdings [Member]
Variable Interest Entities [Line Items]
Equity method investment		1,255		1,271
San Diego Gas and Electric Company [Member]
Variable Interest Entities [Line Items]
Operation and maintenance		286	248
Depreciation and amortization		186	166
Operating income		262	248
Interest expense		(103)	(52)
Income from continuing operations before income taxes and equity earnings (losses) of unconsolidated entities		182	225
Income tax expense		(5)	(56)
Net income		177	169
(Earnings) losses attributable to noncontrolling interest		$ (1)	1
San Diego Gas and Electric Company [Member] | Otay Mesa VIE [Member]
Variable Interest Entities [Line Items]
Generating capacity | MW		605
Conditional purchase obligation		$ 280
Equity of variable interest entity		102		$ 100
Secured debt of variable interest entity		220
Cost of electric fuel and purchased power		(16)	(16)
Operation and maintenance		4	4
Depreciation and amortization		7	8
Total operating expenses		(5)	(4)
Operating income		5	4
Interest expense		(4)	(5)
Net income		1	(1)
(Earnings) losses attributable to noncontrolling interest		(1)	1
Earnings attributable to common shares		$ 0	$ 0
Oncor Holdings [Member] | Sempra Texas Holdings Corp [Member] | Sempra Texas Intermediate Holding Company LLC [Member]
Variable Interest Entities [Line Items]
Ownership percentage in consolidated entity	100.00%
Oncor Electric Delivery Company LLC. [Member]
Variable Interest Entities [Line Items]
Acquired percentage interest	80.25%
Oncor Electric Delivery Company LLC. [Member] | Sempra Texas Holdings Corp [Member]
Variable Interest Entities [Line Items]
Acquired percentage interest	80.03%

[1] Derived from audited financial statements.