NUCLEAR PLANT - COST STUDY (Details) $ in Millions	3 Months Ended
	Mar. 31, 2016 USD ($)
SDG&E Ownership [Member]
Environmental Exit Cost [Line Items]
Total Estimated Nuclear Decommissioning Costs, Latest Cost Study	$ 899
SDG&E Ownership [Member] | San Diego Gas and Electric Company [Member]
Environmental Exit Cost [Line Items]
Total Estimated Nuclear Decommissioning Costs, Latest Cost Study	899
Total Ownership [Member]
Environmental Exit Cost [Line Items]
Total Estimated Nuclear Decommissioning Costs, Latest Cost Study	4,411
Total Ownership [Member] | San Diego Gas and Electric Company [Member]
Environmental Exit Cost [Line Items]
Total Estimated Nuclear Decommissioning Costs, Latest Cost Study	$ 4,411