OTHER FINANCIAL DATA - SHAREHOLDER'S EQUITY AND NONCONTROLLING INTEREST (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016		Jun. 30, 2015
Equity, beginning of period				$ 12,579	[1]	$ 12,100
Comprehensive income (loss)				312		667
Share-based compensation expense				24		26
Common stock dividends declared				(377)		(347)
Preferred dividends of subsidiary		$ (1)	$ (1)	(1)		(1)
Issuance of common stock				56		59
Repurchases of common stock				(54)		(66)
Tax benefit related to share-based compensation				34		52
Equity contributed by noncontrolling interest				1		1
Distributions to noncontrolling interests				(11)		(16)
Equity, end of period		12,563	12,475	12,563		12,475
San Diego Gas and Electric Company [Member]
Equity, beginning of period				5,276	[1]	4,992
Comprehensive income (loss)				216		282
Common stock dividends declared				(175)
Distributions to noncontrolling interests				(3)		(8)
Equity, end of period		5,314	5,266	5,314		5,266
Southern California Gas Company [Member]
Equity, beginning of period				3,149	[1]	2,781
Comprehensive income (loss)				195		285
Preferred dividend requirements		1	1	1		1
Equity, end of period		3,343	3,065	3,343		3,065
Total Shareholders' Equity [Member]
Equity, beginning of period				11,809		11,326
Comprehensive income (loss)				290		634
Share-based compensation expense				24		26
Common stock dividends declared				(377)		(347)
Preferred dividends of subsidiary				(1)		(1)
Issuance of common stock				56		59
Repurchases of common stock				(54)		(66)
Tax benefit related to share-based compensation				34		52
Equity contributed by noncontrolling interest				0		0
Distributions to noncontrolling interests				0		0
Equity, end of period		11,781	11,683	11,781		11,683
Total Shareholders' Equity [Member] | San Diego Gas and Electric Company [Member]
Equity, beginning of period				5,223		4,932
Comprehensive income (loss)				229		273
Common stock dividends declared				(175)
Distributions to noncontrolling interests				0		0
Equity, end of period		5,277	5,205	5,277		5,205
Noncontrolling Interests [Member]
Equity, beginning of period	[2]			770		774
Comprehensive income (loss)	[2]			22		33
Share-based compensation expense	[2]			0		0
Common stock dividends declared	[2]			0		0
Preferred dividends of subsidiary	[2]			0		0
Issuance of common stock	[2]			0		0
Repurchases of common stock	[2]			0		0
Tax benefit related to share-based compensation	[2]			0		0
Equity contributed by noncontrolling interest	[2]			1		1
Distributions to noncontrolling interests	[2]			(11)		(16)
Equity, end of period	[2]	782	792	782		792
Noncontrolling Interests [Member] | San Diego Gas and Electric Company [Member]
Equity, beginning of period				53		60
Comprehensive income (loss)				(13)		9
Common stock dividends declared				0
Distributions to noncontrolling interests				(3)		(8)
Equity, end of period		$ 37	$ 61	$ 37		$ 61

[1] Derived from audited financial statements.

[2] Noncontrolling interests include the preferred stock of SoCalGas and other noncontrolling interests as listed in the table below under "Other Noncontrolling Interests."