CALIFORNIA UTILITIES' REGULATORY MATTERS - NUCLEAR PLANT (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2013		Dec. 31, 2012	Dec. 31, 2013
San Diego Gas and Electric Company and Subsidiary [Member]
Nuclear Plant Investment [Line Items]
Nuclear Plant, Net Book Investment, Plant	$ 393	[1]
Nuclear Plant, Net Book Investment, Materials	10	[1]
Nuclear Plant, Net Book Investment, Nuclear Fuel	116	[1]
Nuclear Plant, Net Book Investment, Total	519	[1]
Nuclear Plant, Rate Base Investment	271	[1]
San Diego Gas and Electric Company and Subsidiary [Member] | Unit 2 [Member]
Nuclear Plant Investment [Line Items]
Nuclear Plant, Net Book Investment, Plant	151	[1]
Nuclear Plant, Net Book Investment, Total	151	[1]
Nuclear Plant, Rate Base Investment	99	[1]
San Diego Gas and Electric Company and Subsidiary [Member] | Unit 3 [Member]
Nuclear Plant Investment [Line Items]
Nuclear Plant, Net Book Investment, Plant	115	[1]
Nuclear Plant, Net Book Investment, Total	115	[1]
Nuclear Plant, Rate Base Investment	94	[1]
San Diego Gas and Electric Company and Subsidiary [Member] | Common Plant [Member]
Nuclear Plant Investment [Line Items]
Nuclear Plant, Net Book Investment, Plant	127	[1]
Nuclear Plant, Net Book Investment, Materials	10	[1]
Nuclear Plant, Net Book Investment, Nuclear Fuel	116	[1]
Nuclear Plant, Net Book Investment, Total	253	[1]
Nuclear Plant, Rate Base Investment	78	[1]
Nuclear Plant, SDGE [Member]
Nuclear Plant [Line Items]
Nuclear Plant, Ownership Percentage	20.00%
Nuclear Plant, Proportional Investment	149
Nuclear Plant, Replacement Power Costs	35			107
Nuclear Plant, MHI Limited Liability	138
Nuclear Plant, Revenue Recognized Associated with SONGS	39		199
Nuclear Plant, Invoice to MHI	139
Nuclear Plant, Invoice Paid By MHI	45
Partial Proof Of Loss Submitted to Nuclear Electric Insurance Limited	$ 234

[1] Excludes nuclear decommissioning-related assets and liabilities.