OTHER FINANCIAL DATA - OTHER INCOME (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Other Income [Line Items]
Allowance for equity funds used during construction	$ 72	$ 27
Investment gains	16	10
Gains on interest rate and foreign exchange instruments, net	63	3
Foreign currency transaction gains (losses)	10	(2)
Sale of other investments	0	1
Electrical infrastructure relocation income	0	1
Regulatory Interest, net	2	2
Sundry, net	6	7
Total	169	49	[1]
San Diego Gas and Electric Company [Member]
Other Income [Line Items]
Allowance for equity funds used during construction	15	11
Regulatory Interest, net	2	2
Sundry, net	1	1
Total	18	14	[1]
Southern California Gas Company [Member]
Other Income [Line Items]
Allowance for equity funds used during construction	11	10
Total	$ 11	$ 10	[1]

[1] As adjusted for the adoption of ASU 2016-09 as of January 1, 2016.