OTHER FINANCIAL DATA - INCOME TAXES (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Income Tax Expense And Effective Income Tax Rates Disclosure [Line Items]
Income tax expense (benefit)	$ 92	$ 59	$ 201	$ 117
Effective income tax rate	16.00%	25.00%	22.00%	31.00%
Remeasurement of equity method investments	277		277
Income tax expense (benefit) due to Mexican currency translation and inflation adjustments	2	(4)
Write-down of deferred tax assets related to other post retirement benefits				16
San Diego Gas and Electric Company and Subsidiary [Member]
Income Tax Expense And Effective Income Tax Rates Disclosure [Line Items]
Income tax expense (benefit)	42	44	91	75
Effective income tax rate	44.00%	44.00%	38.00%	36.00%
Write-down of deferred tax assets related to other post retirement benefits				3
Southern California Gas Company [Member]
Income Tax Expense And Effective Income Tax Rates Disclosure [Line Items]
Income tax expense (benefit)	28	34	65	90
Effective income tax rate	32.00%	33.00%	34.00%	40.00%
Write-down of deferred tax assets related to other post retirement benefits				$ 13