REVENUES - CONTRACT LIABILITIES (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Contract with Customer, Liability [Roll Forward]
Contract liabilities, opening balance	$ (70)	$ 0
Adoption of ASC 606 adjustment		(61)
Revenue from performance obligations satisfied during reporting period	1	6
Payments received in advance	(95)	(9)
Contract liabilities, closing balance	(164)	(64)
Deferred Credits and Other [Member]
Contract with Customer, Liability [Roll Forward]
Contract liabilities, closing balance	(161)
San Diego Gas and Electric Company [Member]
Contract with Customer, Liability [Roll Forward]
Contract liabilities, opening balance	0
Revenue from performance obligations satisfied during reporting period	0
Payments received in advance	(92)
Contract liabilities, closing balance	(92)	0
San Diego Gas and Electric Company [Member] | Other Current Liabilities [Member]
Contract with Customer, Liability [Roll Forward]
Contract liabilities, closing balance	(3)
San Diego Gas and Electric Company [Member] | Deferred Credits and Other [Member]
Contract with Customer, Liability [Roll Forward]
Contract liabilities, closing balance	(89)
Southern California Gas Company [Member]
Contract with Customer, Liability [Roll Forward]
Contract liabilities, closing balance	$ 0	$ 0