OTHER FINANCIAL DATA - CAPITALIZED FINANCING COSTS (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Capitalized Financing Costs Disclosure [Line Items]
AFUDC related to debt	$ 13	$ 9	$ 27	$ 17
AFUDC related to equiity	32	22	67	41
Other capitalized financing costs	16	8	27	14
Total capitalized financing costs	61	39	121	72
San Diego Gas and Electric Company and Subsidiary [Member]
Capitalized Financing Costs Disclosure [Line Items]
AFUDC related to debt	11	8	23	14
AFUDC related to equiity	26	18	55	33
Total capitalized financing costs	37	26	78	47
Southern California Gas Company [Member]
Capitalized Financing Costs Disclosure [Line Items]
AFUDC related to debt	2	1	4	3
AFUDC related to equiity	6	4	12	8
Total capitalized financing costs	$ 8	$ 5	$ 16	$ 11