REVENUES - CONTRACT LIABILITIES (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Contract with Customer, Liability [Roll Forward]
Contract liabilities, opening balance	$ (163)	$ (70)
Revenue from performance obligations satisfied during reporting period	2	1
Payments received in advance		(3)
Contract liabilities, closing balance	(161)	$ (72)
Other Current Liabilities [Member]
Contract with Customer, Liability [Roll Forward]
Contract liabilities, closing balance	(4)
Deferred Credits and Other [Member]
Contract with Customer, Liability [Roll Forward]
Contract liabilities, closing balance	(157)
San Diego Gas and Electric Company [Member]
Contract with Customer, Liability [Roll Forward]
Contract liabilities, opening balance	(91)
Revenue from performance obligations satisfied during reporting period	2
Contract liabilities, closing balance	(89)
San Diego Gas and Electric Company [Member] | Other Current Liabilities [Member]
Contract with Customer, Liability [Roll Forward]
Contract liabilities, closing balance	(4)
San Diego Gas and Electric Company [Member] | Deferred Credits and Other [Member]
Contract with Customer, Liability [Roll Forward]
Contract liabilities, closing balance	$ (85)