OTHER FINANCIAL DATA - CAPITALIZED FINANCING COSTS (Details) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Capitalized Financing Costs Disclosure [Line Items]
AFUDC related to debt	$ 10	$ 6	$ 27	$ 16
AFUDC related to equiity	26	13	67	40
Other capitalized financing costs	6	9	20	27
Total capitalized financing costs	42	28	114	83
San Diego Gas and Electric Company and Subsidiary [Member]
Capitalized Financing Costs Disclosure [Line Items]
AFUDC related to debt	8	5	22	12
AFUDC related to equiity	21	11	54	30
Total capitalized financing costs	29	16	76	42
Southern California Gas Company [Member]
Capitalized Financing Costs Disclosure [Line Items]
AFUDC related to debt	2	1	5	4
AFUDC related to equiity	5	2	13	10
Total capitalized financing costs	$ 7	$ 3	$ 18	$ 14

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- Definition

The amount of interest that was capitalized during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 34

-Paragraph 21

-Subparagraph b

+ Details

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- Definition

The component of the allowance for funds used during construction during the period based on an assumed rate of return on equity funds used in financing the construction of regulated assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 71

-Paragraph 15

+ Details

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- Definition

The component of the allowance for funds used during construction during the period comprised of interest on borrowed funds used in financing the construction of regulated assets, which may be reflected as a reduction of interest expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 71

-Paragraph 15

+ Details

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