OTHER FINANCIAL DATA - OTHER INCOME (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012		Jun. 30, 2013		Jun. 30, 2012
Component of Other Income, Nonoperating [Line Items]
Other income (expense), net	$ 26		$ 18		$ 63		$ 93
San Diego Gas and Electric Company and Subsidiary [Member]
Component of Other Income, Nonoperating [Line Items]
Other income (expense), net	9		24		20		54
Southern California Gas Company [Member]
Component of Other Income, Nonoperating [Line Items]
Other income (expense), net	3		4		7		8
Allowance for Cost of Equity Funds Used During Construction [Member]
Component of Other Income, Nonoperating [Line Items]
Other income (expense), net	15		32		30		67
Allowance for Cost of Equity Funds Used During Construction [Member] | San Diego Gas and Electric Company and Subsidiary [Member]
Component of Other Income, Nonoperating [Line Items]
Other income (expense), net	10		26		20		55
Allowance for Cost of Equity Funds Used During Construction [Member] | Southern California Gas Company [Member]
Component of Other Income, Nonoperating [Line Items]
Other income (expense), net	5		6		10		12
Regulatory Interest, Net [Member]
Component of Other Income, Nonoperating [Line Items]
Other income (expense), net	1	[1]			2	[1]	1	[1]
Regulatory Interest, Net [Member] | San Diego Gas and Electric Company and Subsidiary [Member]
Component of Other Income, Nonoperating [Line Items]
Other income (expense), net	1	[1]			2	[1]	1	[1]
Gains (losses) on interest rate and foreign exchange instruments [Member]
Component of Other Income, Nonoperating [Line Items]
Other income (expense), net	6		(1)		13		10
Gain (Loss) on Investments [Member]
Component of Other Income, Nonoperating [Line Items]
Other income (expense), net	12	[2]	(9)	[2]	22	[2]	10	[2]
Other Income, Sundry [Member]
Component of Other Income, Nonoperating [Line Items]
Other income (expense), net	(8)		(4)		(4)		5
Other Income, Sundry [Member] | San Diego Gas and Electric Company and Subsidiary [Member]
Component of Other Income, Nonoperating [Line Items]
Other income (expense), net	(2)		(2)		(2)		(2)
Other Income, Sundry [Member] | Southern California Gas Company [Member]
Component of Other Income, Nonoperating [Line Items]
Other income (expense), net	$ (2)		$ (2)		$ (3)		$ (4)

[1] Interest on regulatory balancing accounts.

[2] Represents investment gains (losses) on dedicated assets in support of our executive retirement and deferred compensation plans. These amounts are partially offset by corresponding changes in compensation expense related to the plans.