OTHER FINANCIAL DATA - COMPREHENSIVE INCOME AND EQUITY (Details)	0 Months Ended		3 Months Ended		9 Months Ended																						3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended
	Mar. 31, 2013 USD ($)	Mar. 31, 2013 MXN	Sep. 30, 2014 USD ($)	Sep. 30, 2013 USD ($)	Sep. 30, 2014 USD ($)		Sep. 30, 2013 USD ($)	Dec. 31, 2013 USD ($)	Sep. 30, 2014 Ownership Interests Held By Others, Bay Gas Storage Company [Member] USD ($)	Dec. 31, 2013 Ownership Interests Held By Others, Bay Gas Storage Company [Member] USD ($)	Sep. 30, 2014 Ownership Interests Held By Others, Southern Gas Transmission [Member] USD ($)	Dec. 31, 2013 Ownership Interests Held By Others, Southern Gas Transmission [Member] USD ($)	Sep. 30, 2014 Ownership Interests Held By Others, Liberty Gas Storage [Member] USD ($)	Dec. 31, 2013 Ownership Interests Held By Others, Liberty Gas Storage [Member] USD ($)	Sep. 30, 2014 Ownership Interests Held By Others, Tecsur [Member] USD ($)	Dec. 31, 2013 Ownership Interests Held By Others, Tecsur [Member] USD ($)	Sep. 30, 2014 Ownership Interests Held By Others, Luz Del Sur [Member] USD ($)	Dec. 31, 2013 Ownership Interests Held By Others, Luz Del Sur [Member] USD ($)	Sep. 30, 2014 Ownership Interests Held By Others, Chilquinta Energia [Member] USD ($)		Dec. 31, 2013 Ownership Interests Held By Others, Chilquinta Energia [Member] USD ($)		Sep. 30, 2014 Ownership Interests Held By Others, Otay Mesa VIE [Member] USD ($)	Dec. 31, 2013 Ownership Interests Held By Others, Otay Mesa VIE [Member] USD ($)	Sep. 30, 2014 Ownership Interests Held By Others IEnova [Member] USD ($)	Dec. 31, 2013 Ownership Interests Held By Others IEnova [Member] USD ($)	Sep. 30, 2014 San Diego Gas and Electric Company and Subsidiary [Member] USD ($)	Sep. 30, 2013 San Diego Gas and Electric Company and Subsidiary [Member] USD ($)	Sep. 30, 2014 San Diego Gas and Electric Company and Subsidiary [Member] USD ($)		Sep. 30, 2013 San Diego Gas and Electric Company and Subsidiary [Member] USD ($)	Sep. 30, 2014 Southern California Gas Company [Member] USD ($)	Sep. 30, 2013 Southern California Gas Company [Member] USD ($)	Sep. 30, 2014 Southern California Gas Company [Member] USD ($)		Sep. 30, 2013 Southern California Gas Company [Member] USD ($)	Sep. 30, 2014 Total Shareholders' Equity USD ($)	Sep. 30, 2013 Total Shareholders' Equity USD ($)	Sep. 30, 2014 Total Shareholders' Equity San Diego Gas and Electric Company and Subsidiary [Member] USD ($)	Sep. 30, 2013 Total Shareholders' Equity San Diego Gas and Electric Company and Subsidiary [Member] USD ($)	Sep. 30, 2014 Noncontrolling Interests [Member] USD ($)	Sep. 30, 2013 Noncontrolling Interests [Member] USD ($)	Sep. 30, 2014 Noncontrolling Interests [Member] San Diego Gas and Electric Company and Subsidiary [Member] USD ($)	Sep. 30, 2013 Noncontrolling Interests [Member] San Diego Gas and Electric Company and Subsidiary [Member] USD ($)
Comprehensive Income Disclosure [Line Items]
Equity, beginning of period					$ 11,850,000,000	[1]	$ 10,683,000,000																						$ 4,719,000,000	[1]	$ 4,298,000,000			$ 2,549,000,000	[1]	$ 2,235,000,000	$ 11,008,000,000	$ 10,282,000,000	$ 4,628,000,000	$ 4,222,000,000	$ 842,000,000	$ 401,000,000	$ 91,000,000	$ 76,000,000
Comprehensive income (loss)					788,000,000		921,000,000																						404,000,000		309,000,000			259,000,000		268,000,000	722,000,000	888,000,000	381,000,000	294,000,000	66,000,000	33,000,000	23,000,000	15,000,000
Share-based compensation expense					35,000,000		30,000,000																														35,000,000	30,000,000			0	0
Call premium on preferred stock of subsidiary			0	(3,000,000)	0		(3,000,000)																															(3,000,000)				0
Call premium on preferred stock																											0	(3,000,000)	0		(3,000,000)
Common stock dividends declared					(486,000,000)		(460,000,000)																													(50,000,000)	(486,000,000)	(460,000,000)			0	0
Preferred dividend requirements																											0	(2,000,000)	0		(4,000,000)	0	0	(1,000,000)		(1,000,000)				(4,000,000)				0
Preferred dividends of subsidiaries			0	(2,000,000)	(1,000,000)		(5,000,000)																														(1,000,000)	(5,000,000)			0	0
Issuance of common stock					71,000,000		57,000,000																														71,000,000	57,000,000			0	0
Tax benefit related to share-based compensation					22,000,000		30,000,000																														22,000,000	30,000,000			0	0
Repurchases of common stock					(38,000,000)		(45,000,000)																														(38,000,000)	(45,000,000)			0	0
Redemption of preferred stock of subidiary																																								(3,000,000)				0
Sale of noncontrolling interests, net of offering costs							574,000,000																															135,000,000				439,000,000
Noncontrolling Interest Increase					1,000,000																																0				1,000,000
Distributions to noncontrolling interests					(85,000,000)		(28,000,000)																						(37,000,000)		(12,000,000)						0	0	0	0	(85,000,000)	(28,000,000)	(37,000,000)	(12,000,000)
Equity, end of period			12,157,000,000	11,754,000,000	12,157,000,000		11,754,000,000																				5,086,000,000	4,588,000,000	5,086,000,000		4,588,000,000	2,807,000,000	2,452,000,000	2,807,000,000		2,452,000,000	11,333,000,000	10,909,000,000	5,009,000,000	4,509,000,000	824,000,000	845,000,000	77,000,000	79,000,000
Ownership Interests Held By Others [Line Items]
Percent of ownership held by others									9.10%		49.00%		25.00%		9.80%		20.20%						100.00%		18.90%
Percent of ownership held by others, minimum																			23.60%	[2]
Percent of ownership held by others, maximum																			43.40%	[2]
Amount of ownership interests held by others			804,000,000		804,000,000			822,000,000	23,000,000	22,000,000	1,000,000	1,000,000	14,000,000	14,000,000	3,000,000	3,000,000	219,000,000	222,000,000	23,000,000	[2]	27,000,000	[2]	77,000,000	91,000,000	444,000,000	442,000,000
Sale Of Noncontrolling Interests [Abstract]
Proceeds From Sale Of Noncontrolling Interests Net	$ 574,000,000	7,100,000,000			$ 0		$ 574,000,000

[1] Derived from audited financial statements.

[2] Chilquinta Energía has four subsidiaries with noncontrolling interests held by others. Percentage range reflects the highest and lowest ownership percentages amongst these subsidiaries.