OTHER FINANCIAL DATA - VARIABLE INTEREST ENTITIES (Details) $ in Millions	3 Months Ended
	Mar. 31, 2017 USD ($) MW	Mar. 31, 2016 USD ($)		Dec. 31, 2016 USD ($)
Variable Interest Entities [Line Items]
Property, plant and equipment, net	$ 33,492			$ 32,931	[1]
Other noncontrolling interests	2,285			2,270	[1]
Energy-related businesses	333	$ 180	[2]
Operation and maintenance	(714)	(701)	[2]
Depreciation and amortization	(360)	(328)	[2],[3]
Interest expense	(169)	(143)	[2]
Income before income taxes	755	455	[2]
Income tax expense	(295)	(108)	[2]
Income before income taxes/Net income	452	364	[2],[3]
Earnings attributable to noncontrolling interest	(11)	(11)	[2]
Earnings attributable to common shares	441	353	[2]
Otay Mesa VIE [Member]
Variable Interest Entities [Line Items]
Property, plant and equipment, net	342			354
Sempra Renewables [Member] | Tax Equity Investors [Member]
Variable Interest Entities [Line Items]
Property, plant and equipment, net	918			926
Other noncontrolling interests	464			468
Energy-related businesses	13
Operation and maintenance	(2)
Depreciation and amortization	(8)
Income before income taxes	3
Income tax expense	(2)
Income before income taxes/Net income	1
Earnings attributable to noncontrolling interest	3
Earnings attributable to common shares	4
Sempra Natural Gas [Member] | Cameron LNG Holdings [Member]
Investments [Abstract]
Carrying value of equity method investment	999			997
San Diego Gas and Electric Company [Member]
Variable Interest Entities [Line Items]
Property, plant and equipment, net	13,467			13,250	[1]
Other noncontrolling interests	39			37	[1]
Operation and maintenance	227	246	[2]
Depreciation and amortization	163	159	[2],[3]
Operating income	278	236	[2]
Interest expense	(49)	(48)	[2]
Income before income taxes	247	202	[2]
Income tax expense	(90)	(65)	[2]
Income before income taxes/Net income	157	137	[2],[3]
Earnings attributable to noncontrolling interest	$ (2)	(1)	[2]
San Diego Gas and Electric Company [Member] | Otay Mesa VIE [Member]
Variable Interest Entities [Line Items]
Power generating capacity | MW	605
Conditional purchase obligation	$ 280
Equity of variable interest entity	39			37
Secured debt of variable interest entity	302
Property, plant and equipment, net	342			$ 354
Cost of electric fuel and purchased power	(18)	(17)
Operation and maintenance	4	4
Depreciation and amortization	7	7
Total operating expenses	(7)	(6)
Operating income	7	6
Interest expense	(5)	(5)
Income before income taxes/Net income	2	1
Earnings attributable to noncontrolling interest	(2)	(1)
Earnings attributable to common shares	$ 0	$ 0

[1] Derived from audited financial statements.

[2] As adjusted for the adoption of ASU 2016-09 as of January 1, 2016.

[3] As adjusted for the adoption of ASU 2016-09 as of January 1, 2016.