REVENUES - CONTRACT LIABILITIES (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Contract with Customer, Liability [Roll Forward]
Beginning balance	$ (70)	$ 0
Adoption of ASC 606 adjustment		(61)
Revenue from performance obligations satisfied during reporting period	2	7
Payments received in advance	(95)	(16)
Ending balance	(163)	(70)
Other Current Liabilities [Member]
Contract with Customer, Liability [Roll Forward]
Ending balance	(4)
Deferred Credits and Other [Member]
Contract with Customer, Liability [Roll Forward]
Ending balance	(159)
San Diego Gas and Electric Company [Member]
Contract with Customer, Liability [Roll Forward]
Beginning balance	0
Revenue from performance obligations satisfied during reporting period	1
Payments received in advance	(92)
Ending balance	(91)	$ 0
San Diego Gas and Electric Company [Member] | Other Current Liabilities [Member]
Contract with Customer, Liability [Roll Forward]
Ending balance	(4)
San Diego Gas and Electric Company [Member] | Deferred Credits and Other [Member]
Contract with Customer, Liability [Roll Forward]
Ending balance	$ (87)