OTHER FINANCIAL DATA - COMPREHENSIVE INCOME AND EQUITY (Details) In Millions, except Share data, unless otherwise specified	0 Months Ended		3 Months Ended		6 Months Ended																			3 Months Ended		6 Months Ended			3 Months Ended		6 Months Ended			3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended
	Mar. 31, 2013 USD ($)	Mar. 31, 2013 MXN	Jun. 30, 2013 USD ($)	Jun. 30, 2012 USD ($)	Jun. 30, 2013 USD ($)		Jun. 30, 2012 USD ($)	Dec. 31, 2012 USD ($)	Jun. 30, 2013 Ownership Interests Held By Others, Bay Gas Storage Company [Member] USD ($)	Dec. 31, 2012 Ownership Interests Held By Others, Bay Gas Storage Company [Member] USD ($)	Jun. 30, 2013 Ownership Interests Held By Others, Southern Gas Transmission [Member] USD ($)	Dec. 31, 2012 Ownership Interests Held By Others, Southern Gas Transmission [Member] USD ($)	Jun. 30, 2013 Ownership Interests Held By Others, Liberty Gas Storage [Member] USD ($)	Dec. 31, 2012 Ownership Interests Held By Others, Liberty Gas Storage [Member] USD ($)	Jun. 30, 2013 Ownership Interests Held By Others, Tecsur [Member] USD ($)	Dec. 31, 2012 Ownership Interests Held By Others, Tecsur [Member] USD ($)	Jun. 30, 2013 Ownership Interests Held By Others, Luz Del Sur [Member] USD ($)	Dec. 31, 2012 Ownership Interests Held By Others, Luz Del Sur [Member] USD ($)	Jun. 30, 2013 Ownership Interests Held By Others, Chilquinta Energia [Member] USD ($)	Dec. 31, 2012 Ownership Interests Held By Others, Chilquinta Energia [Member] USD ($)	Jun. 30, 2013 Ownership Interests Held By Others, Otay Mesa VIE [Member] USD ($)	Dec. 31, 2012 Ownership Interests Held By Others, Otay Mesa VIE [Member] USD ($)	Jun. 30, 2013 Ownership Interests Held By Others IEnova [Member] USD ($)	Jun. 30, 2013 San Diego Gas and Electric Company and Subsidiary [Member] USD ($)	Jun. 30, 2012 San Diego Gas and Electric Company and Subsidiary [Member] USD ($)	Jun. 30, 2013 San Diego Gas and Electric Company and Subsidiary [Member] USD ($)		Jun. 30, 2012 San Diego Gas and Electric Company and Subsidiary [Member] USD ($)	Jun. 30, 2013 Southern California Gas Company [Member] USD ($)	Jun. 30, 2012 Southern California Gas Company [Member] USD ($)	Jun. 30, 2013 Southern California Gas Company [Member] USD ($)		Jun. 30, 2012 Southern California Gas Company [Member] USD ($)	Jun. 30, 2013 Total Shareholders' Equity USD ($)	Jun. 30, 2012 Total Shareholders' Equity USD ($)	Jun. 30, 2013 Total Shareholders' Equity USD ($)	Jun. 30, 2012 Total Shareholders' Equity USD ($)	Jun. 30, 2013 Total Shareholders' Equity San Diego Gas and Electric Company and Subsidiary [Member] USD ($)	Jun. 30, 2012 Total Shareholders' Equity San Diego Gas and Electric Company and Subsidiary [Member] USD ($)	Jun. 30, 2013 Total Shareholders' Equity San Diego Gas and Electric Company and Subsidiary [Member] USD ($)	Jun. 30, 2012 Total Shareholders' Equity San Diego Gas and Electric Company and Subsidiary [Member] USD ($)	Jun. 30, 2013 Noncontrolling Interests USD ($)	Jun. 30, 2012 Noncontrolling Interests USD ($)	Jun. 30, 2013 Noncontrolling Interests USD ($)	Jun. 30, 2012 Noncontrolling Interests USD ($)	Jun. 30, 2013 Noncontrolling Interests San Diego Gas and Electric Company and Subsidiary [Member] USD ($)	Jun. 30, 2012 Noncontrolling Interests San Diego Gas and Electric Company and Subsidiary [Member] USD ($)	Jun. 30, 2013 Noncontrolling Interests San Diego Gas and Electric Company and Subsidiary [Member] USD ($)	Jun. 30, 2012 Noncontrolling Interests San Diego Gas and Electric Company and Subsidiary [Member] USD ($)
Comprehensive Income And Equity Disclosure [Line Items]
Equity, beginning of period					$ 10,683	[1]	$ 10,178																			$ 4,298	[1]	$ 3,841			$ 2,235	[1]				$ 10,282	$ 9,775			$ 4,222	$ 3,739			$ 401	$ 403			$ 76	$ 102
Comprehensive income, net of income tax
Net income			267	74	445		325																	73	101	154		213	119	54	165		120	246	63	426	301	66	96	158	202	21	11	19	24	7	5	(4)	11
Foreign currency translation adjustments			114	(34)	120		37																											134	(33)	144	34					(20)	(1)	(24)	3
Financial instruments			38	(18)	27		(15)																	12	(9)	15		(9)	1	1	1		1	23	(9)	9	(6)					15	(9)	18	(9)	12	(9)	15	(9)
Net actuarial gain			1	4	4		5																	1		1								1	4	4	5	1		1
Share-based compensation expense					20		24																													20	24
Common stock dividends declared					(307)		(289)																													(307)	(289)
Preferred dividend requirements																								(1)	(1)	(2)		(2)	(1)	(1)	(1)		(1)							(2)	(2)
Preferred dividends of subsidiaries			(1)	(1)	(3)		(3)																											(1)	(1)	(3)	(3)
Issuance of common stock					22		45																													22	45
Tax benefit related to share-based compensation					17																															17
Repurchases of common stock					(45)		(16)																													(45)	(16)
Common stock released from ESOP							9																														9
Sale of noncontrolling interests, net of offering costs					574																															135								439
Equity contributed by noncontrolling interests					4		3																			4																		4	3			4
Distributions to noncontrolling interests					(13)		(10)																			(3)		(1)																(13)	(10)			(3)	(1)
Equity, end of period			11,548	10,293	11,548		10,293																	4,467	4,042	4,467		4,042	2,350		2,350			10,704	9,879	10,704	9,879	4,379	3,939	4,379	3,939	844	414	844	414	88	103	88	103
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																			24.40%
Percent of ownership held by others, maximum																			43.40%
Amount of ownership interests held by others			824		824			381	21	20	1	1	14	15	4	4	221	236	27	29	88	76	448
Sale Of Noncontrolling Interests [Abstract]
Proceeds From Sale Of Noncontrolling Interests Net	$ 574	7,100			$ 574
Common stock shares issued	218,110,500	218,110,500
Share price	$ 2.75	34
Minority interest ownership percentage by parent	81.10%	81.10%
Foreign currency exchange rate pesos to US dollars	12.3841	12.3841

[1] Derived from audited financial statements.