OTHER FINANCIAL DATA - INCOME TAXES (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011		Sep. 30, 2012	Sep. 30, 2011
Income Tax Expense And Effective Income Tax Rates Disclosure [Line Items]
Income tax expense (benefit)	$ 49	$ 75	[1]	$ 48	$ 289	[1]
Effective income tax rate	15.00%	19.00%		8.00%	22.00%
Remeasurement of equity method investments					277	[1]
Income tax benefit associated with life insurance contracts				54
Income tax benefit for repair allowance	38			38
Income tax benefit for repair allowance related to 2011	22			22
San Diego Gas and Electric Company and Subsidiary [Member]
Income Tax Expense And Effective Income Tax Rates Disclosure [Line Items]
Income tax expense (benefit)	38	63		151	154
Effective income tax rate	17.00%	32.00%		27.00%	35.00%
Income tax benefit for repair allowance	38			38
Income tax benefit for repair allowance related to 2011	22			22
Southern California Gas Company [Member]
Income Tax Expense And Effective Income Tax Rates Disclosure [Line Items]
Income tax expense (benefit)	$ 37	$ 41		$ 105	$ 106
Effective income tax rate	34.00%	34.00%		35.00%	34.00%

[1] As adjusted for the retrospective effect of a change in accounting principle as we discuss in Note 1.