NEW ACCOUNTING STANDARDS (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Statement of Cash Flows [Abstract]
Net cash provided by operating activities	$ 2,710	$ 1,691
Effect of exchange rate changes on cash and cash equivalents	9	8
Net cash used in investing activities	(3,260)	(3,432)
Effect of Early Adoption of New Accounting Pronouncement [Member] | ASUs 2016-15 and 2016-18 [Member]
Statement of Cash Flows [Abstract]
Cash, cash equivalents and restricted cash, beginning of period	76
Net cash provided by operating activities	(6)
Effect of exchange rate changes on cash and cash equivalents	2
Cash, cash equivalents and restricted cash, end of period	72
San Diego Gas and Electric Company [Member]
Statement of Cash Flows [Abstract]
Net cash provided by operating activities	1,178	933
Net cash used in investing activities	(1,094)	$ (982)
San Diego Gas and Electric Company [Member] | Effect of Early Adoption of New Accounting Pronouncement [Member] | ASUs 2016-15 and 2016-18 [Member]
Statement of Cash Flows [Abstract]
Cash, cash equivalents and restricted cash, beginning of period	12
Net cash provided by operating activities	(6)
Net cash used in investing activities	9
Cash, cash equivalents and restricted cash, end of period	$ 15