OTHER FINANCIAL DATA - SHARE-BASED COMPENSATION (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense, net of income taxes	$ 7	$ 5	$ 14	$ 11
Restricted stock units issued by IEnova			136,996
Performance-Based [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock units granted			444,241
Service-Based [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock units granted			80,697
Performance-Based, Total Shareholder Return [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock units granted			355,638
Performance-Based, Earnings Per Share [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock units granted			88,603