OTHER FINANCIAL DATA - COMPREHENSIVE INCOME AND EQUITY 3 (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013
Before Tax [Member] | Amortization of Actuarial Loss [Member]
Reclassifications From Accumulated Other Comprehensive Income [Line Items]
Amount Reclassified From Accumulated Other Comprehensive Income Loss	$ 5	[1]
Interest Expense [Member] | Interest Rate Instruments [Member]
Reclassifications From Accumulated Other Comprehensive Income [Line Items]
Amount Reclassified From Accumulated Other Comprehensive Income Loss	3
Interest Expense [Member] | Interest Rate Instruments [Member] | San Diego Gas and Electric Company and Subsidiary [Member]
Reclassifications From Accumulated Other Comprehensive Income [Line Items]
Amount Reclassified From Accumulated Other Comprehensive Income Loss	2
Equity Earnings Before Income Tax [Member] | Interest Rate Instruments [Member]
Reclassifications From Accumulated Other Comprehensive Income [Line Items]
Amount Reclassified From Accumulated Other Comprehensive Income Loss	2
Income Before Tax [Member] | Interest Rate Instruments [Member]
Reclassifications From Accumulated Other Comprehensive Income [Line Items]
Amount Reclassified From Accumulated Other Comprehensive Income Loss	5
Income Tax Expense [Member] | Interest Rate Instruments [Member]
Reclassifications From Accumulated Other Comprehensive Income [Line Items]
Amount Reclassified From Accumulated Other Comprehensive Income Loss	(1)
Income Tax Expense [Member] | Amortization of Actuarial Loss [Member]
Reclassifications From Accumulated Other Comprehensive Income [Line Items]
Amount Reclassified From Accumulated Other Comprehensive Income Loss	(2)	[1]
Income After Tax [Member] | Interest Rate Instruments [Member]
Reclassifications From Accumulated Other Comprehensive Income [Line Items]
Amount Reclassified From Accumulated Other Comprehensive Income Loss	4
Income After Tax [Member] | Amortization of Actuarial Loss [Member]
Reclassifications From Accumulated Other Comprehensive Income [Line Items]
Amount Reclassified From Accumulated Other Comprehensive Income Loss	3	[1]
Earnings Attributable To Noncontrolling Interests [Member] | Interest Rate Instruments [Member]
Reclassifications From Accumulated Other Comprehensive Income [Line Items]
Amount Reclassified From Accumulated Other Comprehensive Income Loss	(2)
Earnings Attributable To Noncontrolling Interests [Member] | Interest Rate Instruments [Member] | San Diego Gas and Electric Company and Subsidiary [Member]
Reclassifications From Accumulated Other Comprehensive Income [Line Items]
Amount Reclassified From Accumulated Other Comprehensive Income Loss	(2)
Total [Member] | Interest Rate Instruments [Member]
Reclassifications From Accumulated Other Comprehensive Income [Line Items]
Amount Reclassified From Accumulated Other Comprehensive Income Loss	$ 2

[1] Amounts are included in the computation of net periodic benefit cost (see "Pension and Other Postretirement Benefits" above).