OTHER FINANCIAL DATA - TRANSACTIONS WITH AFFILIATES 2 (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2015		Sep. 30, 2015		Dec. 31, 2014
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, noncurrent	[1]	$ 178		$ 178		$ 226
Joint venture with PEMEX [Member]
Transactions With Affiliates Disclosure [Line Items]
Interest rate on due from affiliate, noncurrent		4.69%
PEMEX Four year loan C [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, noncurrent	[1],[2],[3]	$ 8		8		8
PEMEX Three year loan A [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, noncurrent	[1],[2],[3]	3	[4]	3	[4]	44
Repayment Of Notes Receivable From Related Parties				41
PEMEX Four year loan B [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, noncurrent	[1],[2],[3]	34		34		33
PEMEX Four year loan A [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, noncurrent	[1],[2],[3]	41		41		40
ESJ joint venture [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, noncurrent	[1],[5]	$ 24		24		22
Interest rate on due from affiliate, noncurrent		6.57%
Eletrans [Member]
Transactions With Affiliates Disclosure [Line Items]
Due from affiliate, noncurrent	[1],[6]	$ 65		65		41
Interest rate on due from affiliate, noncurrent		4.00%
Affiliate Of Investee [Member]
Transactions With Affiliates Disclosure [Line Items]
Due From Joint Ventures Noncurrent	[1],[7]	$ 3		$ 3		$ 38

[1] Amounts include principal balances plus accumulated interest outstanding.

[2] Petróleos Mexicanos (or PEMEX, the Mexican state-owned oil company).

[3] U.S. dollar-denominated loan, at a variable interest rate based on a 30-day LIBOR plus 450 basis points (4.69 percent at September 30, 2015), to finance the Los Ramones Norte pipeline project.

[4] In May 2015, $41 million was paid with proceeds from project financing at the affiliate.

[5] U.S. dollar-denominated loan, at a variable interest rate based on a 30-day LIBOR plus 637.5 basis points (6.57 percent at September 30, 2015), to finance the first phase of the Energía Sierra Juárez wind project.

[6] U.S. dollar-denominated loan, at a fixed interest rate with no stated maturity date, to provide project financing for the construction of transmission lines at Eletrans S.A., an affiliate of Chilquinta Energía.

[7] Amounts represent accounts receivable from various Sempra Renewables and Sempra Mexico joint venture investments.