OTHER FINANCIAL DATA - TRANSACTIONS WITH AFFILIATES (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			9 Months Ended
	Sep. 30, 2011		Sep. 30, 2010	Sep. 30, 2011		Sep. 30, 2010	Dec. 31, 2010
Transactions With Joint Venture [Line Items]
Revenues from transactions with RBS Sempra Commodities			$ 71	$ 44	[1]	$ 226
Cost of natural gas from transactions with RBS Sempra Commodities	3	[1]	110	77	[1]	323
Fixed-price contracts and other derivatives - Net Asset (Liability) - RBS Sempra Commodities							(18)
Due to RBS Sempra Commodities							35
Due from RBS Sempra Commodities							34
Parent Company Member | Affiliate Of Investee [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, current	24			24
Interest rate on due from affiliate, noncurrent	7.246%
San Diego Gas and Electric Company and Subsidiary [Member] | Due to/from Sempra Energy
Transactions With Affiliates Disclosure [Line Items]
Income taxes due from (to) Sempra Energy	84	[2]		84	[2]		25	[2]
Southern California Gas Company [Member] | Due to/from Sempra Energy
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, current	167			167			60
Income taxes due from (to) Sempra Energy	63	[2]		63	[2]		(3)	[2]
Southern California Gas Company [Member] | Subsidiary Of Common Parent S D G E [Member]
Transactions With Affiliates Disclosure [Line Items]
Due to affiliate, current	10			10			11
San Diego Gas and Electric Company and Subsidiary [Member] | Subsdiary Of Common Parent So Cal Gas [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, current	10			10			11
San Diego Gas and Electric Company and Subsidiary [Member] | Subsidiary Of Common Parent Other Affiliates [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, current	1			1			1
Southern California Gas Company [Member] | Subsidiary Of Common Parent Other Affiliates [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, current	1			1			3
San Diego Gas and Electric Company and Subsidiary [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, current	11			11			12
Due to affiliate, current	23			23			16
Revenues from unconsolidated affiliates	3		1	6		6
Southern California Gas Company [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, current	168			168			63
Revenues from unconsolidated affiliates	13		11	38		32
S D G E Segment [Member]
Transactions With Joint Venture [Line Items]
Cost of natural gas from transactions with RBS Sempra Commodities			1			2
So Cal Gas Segment [Member]
Transactions With Joint Venture [Line Items]
Revenues from transactions with RBS Sempra Commodities			1			8
Cost of natural gas from transactions with RBS Sempra Commodities			10			33
Due from RBS Sempra Commodities							3
Sempra Generation Segment [Member]
Transactions With Joint Venture [Line Items]
Revenues from transactions with RBS Sempra Commodities			10	4	[1]	19
Cost of natural gas from transactions with RBS Sempra Commodities			30	30	[1]	58
Fixed-price contracts and other derivatives - Net Asset (Liability) - RBS Sempra Commodities							17
Due to RBS Sempra Commodities							11
Due from RBS Sempra Commodities							13
Sempra Pipelines and Storage Segment [Member]
Transactions With Joint Venture [Line Items]
Cost of natural gas from transactions with RBS Sempra Commodities	3	[1]	6	17	[1]	22
Sempra L N G Segment [Member]
Transactions With Joint Venture [Line Items]
Revenues from transactions with RBS Sempra Commodities			60	40	[1]	199
Cost of natural gas from transactions with RBS Sempra Commodities			63	30	[1]	208
Fixed-price contracts and other derivatives - Net Asset (Liability) - RBS Sempra Commodities							(35)
Due to RBS Sempra Commodities							13
Due from RBS Sempra Commodities							13
All Other Segments [Member]
Transactions With Joint Venture [Line Items]
Due to RBS Sempra Commodities							11
Due from RBS Sempra Commodities							$ 5

[1] With the exception of Sempra Pipelines & Storage, whose contract with RBS Sempra Commodities expired in July 2011, amounts only include activities prior to May 1, 2011, the date by which substantially all the contracts with RBS Sempra Commodities were assigned to buyers of the joint venture businesses.

[2] 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.