COMMITMENTS AND CONTINGENCIES - LEGAL PROCEEDINGS (Details)		1 Months Ended				3 Months Ended
	Apr. 29, 2020 plaintiff lawsuit	Oct. 31, 2018 plaintiff	Aug. 31, 2018 USD ($)	Jan. 31, 2017 lawsuit	Feb. 29, 2016 USD ($)	Mar. 31, 2020 USD ($) lawsuit	Dec. 31, 2019 USD ($)	[1]	Nov. 30, 2017 USD ($)
Loss Contingencies [Line Items]
Liability for legal proceedings						$ 442,000,000
Reserve for Aliso Canyon costs						$ 284,000,000	$ 9,000,000
Consolidated Class Action Complaints [Member]
Loss Contingencies [Line Items]
Number of lawsuits filed | lawsuit				2
Property Class Action [Member]
Loss Contingencies [Line Items]
Number of lawsuits filed | lawsuit				1
Complaints Filed by Public Entities [Member]
Loss Contingencies [Line Items]
Number of lawsuits filed | lawsuit						3
Southern California Gas Company [Member]
Loss Contingencies [Line Items]
Liability for legal proceedings						$ 297,000,000
Insurance settlements receivable						1,277,000,000
Reserve for Aliso Canyon costs						284,000,000	$ 9,000,000
Southern California Gas Company [Member] | Aliso Canyon Natural Gas Storage Facility Gas Leak [Member]
Loss Contingencies [Line Items]
Liability for legal proceedings						286,000,000
Loss contingency accrual						1,408,000,000			$ 277,000,000
Net book value of Aliso Canyon facility						771,000,000
Payable related to natural gas leak, noncurrent						284,000,000
Receivable related to natural gas leak						511,000,000
Insurance proceeds						$ 766,000,000
Southern California Gas Company [Member] | Shareholder Derivative Complaint [Member]
Loss Contingencies [Line Items]
Number of lawsuits | lawsuit						4
Southern California Gas Company [Member] | Damages from Product Defects [Member]
Loss Contingencies [Line Items]
Maximum occupational safety and health fines					$ 75,000
Penalty assessments					233,500
Reimbursement costs					246,673
Maximum other assessments in settlement of criminal complaint					$ 6,000,000
Southern California Gas Company [Member] | Complaints Filed by Firefighters [Member] | Aliso Canyon Natural Gas Storage Facility Gas Leak [Member]
Loss Contingencies [Line Items]
Number of plaintiffs | plaintiff		51
Southern California Gas Company [Member] | Complaints Filed by Public Entities [Member] | Funding for Environmental Projects [Member]
Loss Contingencies [Line Items]
Settlement amount payable			$ 120,000,000
Southern California Gas Company [Member] | Complaints Filed by Public Entities [Member] | Civil Penalties [Member]
Loss Contingencies [Line Items]
Settlement amount payable			$ 21,000,000
Subsequent Event [Member] | Southern California Gas Company [Member] | Aliso Canyon Natural Gas Storage Facility Gas Leak [Member]
Loss Contingencies [Line Items]
Number of lawsuits | lawsuit	393
Number of plaintiffs | plaintiff	36,000
Subsequent Event [Member] | Energy Future Holdings Corp. [Member]
Loss Contingencies [Line Items]
Number of lawsuits | lawsuit	275
Number of lawsuits filed | lawsuit	182
Deferred Credits and Other [Member] | Southern California Gas Company [Member] | Aliso Canyon Natural Gas Storage Facility Gas Leak [Member]
Loss Contingencies [Line Items]
Reserve for Aliso Canyon costs						$ 6,000,000

[1] Derived from audited financial statements.