COMMITMENTS AND CONTINGENCIES - RENT EXPENSE OPERATING LEASES (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Operating Leased Assets [Line Items]
Rent expense	$ 122	$ 107
Capital lease depreciation expense	11	8
Depreciation expense on leases	8	3
San Diego Gas and Electric Company [Member]
Operating Leased Assets [Line Items]
Rent expense	27	28
Depreciation expense on leases	2	1
Southern California Gas Company [Member]
Operating Leased Assets [Line Items]
Rent expense	41	43
Depreciation expense on leases	$ 6	$ 2