GENERAL INFORMATION AND OTHER FINANCIAL DATA - OTHER NONCONTROLLING INTERESTS (Details) $ in Millions	1 Months Ended	3 Months Ended
	Apr. 30, 2018 USD ($)	Dec. 31, 2017 USD ($) facility		Jun. 30, 2018 USD ($) subsidiary
Noncontrolling Interest [Line Items]
Noncontrolling interests		$ 2,450	[1]	$ 2,518
San Diego Gas and Electric Company [Member] | Otay Mesa VIE [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests		100.00%		100.00%
Noncontrolling interests		$ 28		$ 29
Sempra South American Utilities [Member] | Chilquinta Energía subsidiaries [Member]
Noncontrolling Interest [Line Items]
Noncontrolling interests		$ 24		$ 23
Number of subsidiaries with noncontrolling interests | subsidiary				4
Sempra South American Utilities [Member] | Chilquinta Energía subsidiaries [Member] | Minimum [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests		22.90%		19.80%
Sempra South American Utilities [Member] | Chilquinta Energía subsidiaries [Member] | Maximum [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests		43.40%		43.40%
Sempra South American Utilities [Member] | Luz del Sur [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests		16.40%		16.40%
Noncontrolling interests		$ 189		$ 192
Sempra South American Utilities [Member] | Tecsur [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests		9.80%		9.80%
Noncontrolling interests		$ 4		$ 4
Sempra Mexico [Member] | IEnova [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests		33.60%		33.60%
Noncontrolling interests		$ 1,532		$ 1,605
Sempra Renewables [Member] | Tax equity arrangement – wind [Member]
Noncontrolling Interest [Line Items]
Noncontrolling interests		181		160
Sempra Renewables [Member] | Tax equity arrangement – solar [Member]
Noncontrolling Interest [Line Items]
Noncontrolling interests		$ 450		$ 509
Sempra LNG & Midstream [Member] | Bay Gas Storage Company, Ltd. [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests		9.10%		9.10%
Noncontrolling interests		$ 28		$ 8
Sempra LNG & Midstream [Member] | Liberty Gas Storage, LLC [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests		24.60%		24.60%
Noncontrolling interests		$ 14		$ (12)
Solar Power Projects [Member] | Tax Equity Investors [Member] | Sempra Renewables [Member]
Noncontrolling Interest [Line Items]
Number of facilities acquired | facility		4
Additional funding	$ 85
Subsidiaries [Member] | Sempra Mexico [Member] | IEnova [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests		10.00%

[1] Derived from audited financial statements.