SIGNIFICANT ACCOUNTING POLICIES AND OTHER FINANCIAL DATA - RESTRICTED NET ASSETS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Oct. 31, 2019	Jan. 01, 2019
Significant Restrictions of Subsidiaries [Line Items]
Undistributed earnings of equity investments	$ 634
Sempra Texas Utilities [Member] | Oncor Electric Delivery Holdings Company LLC [Member]
Significant Restrictions of Subsidiaries [Line Items]
Maximum ratio of indebtedness to total capitalization	0.65
Ownership percentage in equity method investee	100.00%
Plan percentage of capital structure allocated to debt	57.50%
Plan percentage of capital structure allocated to equity	42.50%
Sempra Texas Utilities [Member] | Oncor Electric Delivery Company LLC [Member]
Significant Restrictions of Subsidiaries [Line Items]
Ownership percentage in equity method investee	80.25%
Sempra Mexico [Member] | Mexican Subsidiaries [Member]
Significant Restrictions of Subsidiaries [Line Items]
Restricted net assets of consolidated or unconsolidated subsidiaries	$ 178
Sempra Mexico [Member] | IEnova Pipelines [Member]
Significant Restrictions of Subsidiaries [Line Items]
Restricted net assets of consolidated or unconsolidated subsidiaries	17
Sempra Mexico [Member] | Ventika [Member]
Significant Restrictions of Subsidiaries [Line Items]
Restricted net assets of consolidated or unconsolidated subsidiaries	14
Sempra Mexico [Member] | Energia Sierra Juarez Wind Project [Member]
Significant Restrictions of Subsidiaries [Line Items]
Restricted net assets of consolidated or unconsolidated subsidiaries	$ 15
Ownership percentage in equity method investee	50.00%
Sempra Mexico [Member] | TAG Pipeline Norte [Member]
Significant Restrictions of Subsidiaries [Line Items]
Restricted net assets of consolidated or unconsolidated subsidiaries	$ 171
Ownership percentage in equity method investee	50.00%
Sempra LNG [Member] | Cameron LNG Holdings [Member]
Significant Restrictions of Subsidiaries [Line Items]
Restricted net assets of consolidated or unconsolidated subsidiaries	$ 10,300
Consolidated Entities [Member]
Significant Restrictions of Subsidiaries [Line Items]
Restricted net assets of consolidated or unconsolidated subsidiaries	10,400
Unconsolidated Entities [Member]
Significant Restrictions of Subsidiaries [Line Items]
Restricted net assets of consolidated or unconsolidated subsidiaries	21,500
San Diego Gas and Electric Company [Member]
Significant Restrictions of Subsidiaries [Line Items]
Restricted net assets of consolidated or unconsolidated subsidiaries	6,200
Amount available for dividend distribution and loans without prior approval from regulatory agency	$ 885
Authorized percentage of equity	52.00%
Minimum common equity ratio		10.60%	11.20%
Southern California Gas Company [Member]
Significant Restrictions of Subsidiaries [Line Items]
Restricted net assets of consolidated or unconsolidated subsidiaries	$ 4,000
Amount available for dividend distribution and loans without prior approval from regulatory agency	$ 742
Authorized percentage of equity	52.00%
California Utilities [Member]
Significant Restrictions of Subsidiaries [Line Items]
Maximum ratio of indebtedness to total capitalization	0.65
Sempra Texas Utilities [Member] | Sharyland Holdings, LP [Member]
Significant Restrictions of Subsidiaries [Line Items]
Ownership percentage in equity method investee	50.00%
Sempra Texas Utilities [Member] | Sharyland Utilities [Member]
Significant Restrictions of Subsidiaries [Line Items]
Restricted net assets of consolidated or unconsolidated subsidiaries	$ 115
Maximum ratio of indebtedness to total capitalization	0.70
Ownership percentage in equity method investee	100.00%
Plan percentage of capital structure allocated to debt	55.00%
Plan percentage of capital structure allocated to equity	45.00%
Oncor Electric Delivery Company LLC [Member]
Significant Restrictions of Subsidiaries [Line Items]
Restricted net assets of consolidated or unconsolidated subsidiaries	$ 10,900