NEW ACCOUNTING STANDARDS (Details) - USD ($) shares in Thousands, $ in Millions	3 Months Ended				6 Months Ended	9 Months Ended
	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Sep. 30, 2015	Jun. 30, 2016	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative-effect adjustment								$ 107
Net cash provided by financing activities						$ 1,848	$ 29
Net cash provided by operating activities						$ 1,691	$ 2,089
Reduction in weighted-average common shares outstanding for diluted EPS (in shares)	(252,405)			(251,024)		(251,976)	(250,665)
San Diego Gas and Electric Company [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative-effect adjustment								23
Net cash provided by financing activities						$ 52	$ (272)
Net cash provided by operating activities						933	1,094
Southern California Gas Company [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative-effect adjustment								15
Net cash provided by financing activities						491	544
Net cash provided by operating activities						409	$ 690
Effect of Early Adoption of New Accounting Pronouncement [Member] | Accounting Standards Update 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Excess tax benefits						34
Net cash provided by financing activities						(34)
Net cash provided by operating activities						34
Reduction in weighted-average common shares outstanding for diluted EPS (in shares)		(98)	(75)		(89)
Deferred tax assets, net								107
Effect of Early Adoption of New Accounting Pronouncement [Member] | Accounting Standards Update 2016-09 [Member] | San Diego Gas and Electric Company [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Excess tax benefits						7
Net cash provided by operating activities						7
Deferred tax assets, net								23
Effect of Early Adoption of New Accounting Pronouncement [Member] | Accounting Standards Update 2016-09 [Member] | Southern California Gas Company [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Excess tax benefits						4
Net cash provided by operating activities						$ 4
Deferred tax assets, net								15
Effect of Early Adoption of New Accounting Pronouncement [Member] | Retained Earnings [Member] | Accounting Standards Update 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative-effect adjustment								107
Effect of Early Adoption of New Accounting Pronouncement [Member] | Retained Earnings [Member] | Accounting Standards Update 2016-09 [Member] | San Diego Gas and Electric Company [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative-effect adjustment								23
Effect of Early Adoption of New Accounting Pronouncement [Member] | Retained Earnings [Member] | Accounting Standards Update 2016-09 [Member] | Southern California Gas Company [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative-effect adjustment								$ 15