OTHER FINANCIAL DATA - TRANSACTIONS WITH AFFILIATES (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012	Sep. 30, 2013		Sep. 30, 2012	Dec. 31, 2012
San Diego Gas and Electric Company and Subsidiary [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, current	$ 1			$ 1			$ 39
Due to affiliate, current	13			13			19
Revenues from unconsolidated affiliates	3		2	8		6
Southern California Gas Company [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, current	14			14			24
Due to affiliate, current	20			20			37
Revenues from unconsolidated affiliates	17		17	48		48
Affiliate Of Investee [Member] | Parent Company Member
Transactions With Affiliates Disclosure [Line Items]
Interest rate on due from affiliate, noncurrent
Loan to unconsolidated affiliate, principal
Loan to unconsolidated affiliate, accrued interest
Due to/from Sempra Energy | San Diego Gas and Electric Company and Subsidiary [Member]
Transactions With Affiliates Disclosure [Line Items]
Due to affiliate, current	11			11			19
Income taxes due from (to) Sempra Energy	(2)	[1]		(2)	[1]		12	[1]
Due to/from Sempra Energy | Southern California Gas Company [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, current	12			12			24
Income taxes due from (to) Sempra Energy	130	[1]		130	[1]		99	[1]
Subsidiary Of Common Parent S D G E [Member] | Southern California Gas Company [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, current	2			2			0
Due to affiliate, current	0			0			37
Subsdiary Of Common Parent So Cal Gas [Member] | San Diego Gas and Electric Company and Subsidiary [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, current	0			0			37
Due to affiliate, current	2			2			0
Subsidiary Of Common Parent Other Affiliates [Member] | San Diego Gas and Electric Company and Subsidiary [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, current	1			1			2
Subsidiary Of Common Parent Other Affiliates [Member] | Southern California Gas Company [Member]
Transactions With Affiliates Disclosure [Line Items]
Due to affiliate, current	$ 20			$ 20			$ 0

[1] SDG&E and SoCalGas are included in the consolidated income tax return of Sempra Energy and are allocated income tax expense from Sempra Energy in an amount equal to that which would result from the companies’ having always filed a separate return.