SIGNIFICANT ACCOUNTING POLICIES AND OTHER FINANCIAL DATA - OTHER NONCONTROLLING INTERESTS (Details) $ in Millions	Dec. 31, 2018 USD ($) subsidiary	Dec. 31, 2017 USD ($)
Noncontrolling Interest [Line Items]
Other noncontrolling interests	$ 2,090	$ 2,450
SDG&E [Member] | Otay Mesa VIE [Member]
Noncontrolling Interest [Line Items]
Ownership percentage held by noncontrolling owners	100.00%	100.00%
Other noncontrolling interests	$ 100	$ 28
Sempra South American Utilities [Member] | Chilquinta Energia subsidiaries [Member]
Noncontrolling Interest [Line Items]
Other noncontrolling interests	$ 23	$ 24
Number of subsidiaries with noncontrolling interests | subsidiary	4
Sempra South American Utilities [Member] | Chilquinta Energia subsidiaries [Member] | Minimum [Member]
Noncontrolling Interest [Line Items]
Ownership percentage held by noncontrolling owners	19.70%	22.90%
Sempra South American Utilities [Member] | Chilquinta Energia subsidiaries [Member] | Maximum [Member]
Noncontrolling Interest [Line Items]
Ownership percentage held by noncontrolling owners	43.40%	43.40%
Sempra South American Utilities [Member] | Luz Del Sur [Member]
Noncontrolling Interest [Line Items]
Ownership percentage held by noncontrolling owners	16.40%	16.40%
Other noncontrolling interests	$ 193	$ 189
Sempra South American Utilities [Member] | Tecsur [Member]
Noncontrolling Interest [Line Items]
Ownership percentage held by noncontrolling owners	9.80%	9.80%
Other noncontrolling interests	$ 4	$ 4
Sempra Mexico [Member] | IEnova [Member]
Noncontrolling Interest [Line Items]
Ownership percentage held by noncontrolling owners	33.50%	33.60%
Other noncontrolling interests	$ 1,605	$ 1,532
Sempra Renewables [Member] | Tax equity arrangement – wind [Member]
Noncontrolling Interest [Line Items]
Other noncontrolling interests	$ 158	181
Sempra Renewables [Member] | Tax equity arrangement – solar [Member]
Noncontrolling Interest [Line Items]
Ownership percentage held by noncontrolling owners	0.00%
Other noncontrolling interests	$ 0	$ 450
Sempra Renewables [Member] | PXISE Energy Solutions LLC [Member]
Noncontrolling Interest [Line Items]
Ownership percentage held by noncontrolling owners	11.10%	0.00%
Other noncontrolling interests	$ 1	$ 0
Sempra LNG & Midstream [Member] | Bay Gas Storage Company [Member]
Noncontrolling Interest [Line Items]
Ownership percentage held by noncontrolling owners	9.10%	9.10%
Other noncontrolling interests	$ 18	$ 28
Sempra LNG & Midstream [Member] | Liberty Gas Storage [Member]
Noncontrolling Interest [Line Items]
Ownership percentage held by noncontrolling owners	24.60%	24.60%
Other noncontrolling interests	$ (12)	$ 14
Subsidiaries [Member] | Sempra Mexico [Member] | IEnova subsidiary, one
Noncontrolling Interest [Line Items]
Ownership percentage held by noncontrolling owners	10.00%	10.00%
Subsidiaries [Member] | Sempra Mexico [Member] | IEnova subsidiary, two
Noncontrolling Interest [Line Items]
Ownership percentage held by noncontrolling owners	49.00%
Other noncontrolling interests	$ 13