OTHER FINANCIAL DATA - VARIABLE INTEREST ENTITIES (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) MW	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Variable Interest Entities [Line Items]
Operation and maintenance	$ 703	$ 701	$ 2,109	$ 2,072
Depreciation and amortization	328	315	970	925
Interest expense	(136)	(143)	(421)	(416)
Income (loss) before income taxes/Net income (loss)	719	282	1,110	1,060
(Earnings) losses attributable to noncontrolling interest	(97)	(34)	(118)	(79)
Earnings attributable to common shares	622	248	991	980
Sempra Natural Gas [Member] | Cameron LNG Holdings [Member]
Investments [Abstract]
Carrying value of equity method investment	838		838		$ 983
San Diego Gas and Electric Company [Member]
Variable Interest Entities [Line Items]
Operating income	323	300	729	809
Interest expense	(49)	(51)	(145)	(155)
Income (loss) before income taxes/Net income (loss)	194	182	418	463
(Earnings) losses attributable to noncontrolling interest	(11)	(12)	$ 1	(20)
San Diego Gas and Electric Company [Member] | Otay Mesa VIE [Member]
Variable Interest Entities [Line Items]
Power generating capacity | MW			605
Equity of variable interest entity	50		$ 50		$ 53
Secured debt of variable interest entity	307		307
Cost of electric fuel and purchased power	(28)	(27)	(62)	(66)
Operation and maintenance	4	3	23	13
Depreciation and amortization	8	7	25	19
Total operating expenses	(16)	(17)	(14)	(34)
Operating income	16	17	14	34
Interest expense	(5)	(5)	(15)	(14)
Income (loss) before income taxes/Net income (loss)	11	12	(1)	20
(Earnings) losses attributable to noncontrolling interest	(11)	(12)	1	(20)
Earnings attributable to common shares	$ 0	$ 0	$ 0	$ 0