OTHER FINANCIAL DATA - TRANSACTIONS WITH AFFILIATES (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	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	19			19			19
Revenues from unconsolidated affiliates	3		2	5		4
Southern California Gas Company [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, current	259			259			24
Revenues from unconsolidated affiliates	16		16	31		31
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	17			17			19
Income taxes due from (to) Sempra Energy	1	[1]		1	[1]		12	[1]
Due to/from Sempra Energy | Southern California Gas Company [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, current	257			257			24
Income taxes due from (to) Sempra Energy	132	[1]		132	[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
Due to affiliate, current							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							37
Due to affiliate, current	2			2
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

[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.