GENERAL INFORMATION AND OTHER FINANCIAL DATA - OTHER NONCONTROLLING INTERESTS (Details) - USD ($) $ in Millions	Sep. 30, 2020	Mar. 30, 2020	Dec. 31, 2019
Noncontrolling Interest [Line Items]
Other noncontrolling interests	$ 1,608		$ 1,856	[1]
IEnova [Member] | Sempra Mexico [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests	30.80%		33.40%
Other noncontrolling interests	$ 1,586		$ 1,608
IEnova subsidiaries [Member] | Sempra Mexico [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests	17.50%
Other noncontrolling interests	$ 7		$ 15
IEnova subsidiaries [Member] | Sempra Mexico [Member] | Minimum [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests			10.00%
IEnova subsidiaries [Member] | Sempra Mexico [Member] | Maximum [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests			46.30%
Liberty Gas Storage, LLC [Member] | Sempra LNG [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests	0.00%	24.60%	24.60%
Other noncontrolling interests	$ 0		$ (13)
ECA LNG Proposed Liquefaction Project [Member] | Sempra LNG [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests	15.40%		16.70%
Other noncontrolling interests	$ 15		$ 12
PXISE Energy Solutions LLC [Member] | Parent and Other [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests	20.00%		20.00%
Other noncontrolling interests	$ 0		$ 1
Discontinued Operations, Held-for-sale [Member] | Chilquinta Energía subsidiaries [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests	0.00%
Other noncontrolling interests	$ 0		$ 23
Discontinued Operations, Held-for-sale [Member] | Chilquinta Energía subsidiaries [Member] | Minimum [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests			19.70%
Discontinued Operations, Held-for-sale [Member] | Chilquinta Energía subsidiaries [Member] | Maximum [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests			43.40%
Discontinued Operations, Held-for-sale [Member] | Luz del Sur [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests	0.00%		16.40%
Other noncontrolling interests	$ 0		$ 205
Discontinued Operations, Held-for-sale [Member] | Tecsur [Member]
Noncontrolling Interest [Line Items]
Percent ownership held by noncontrolling interests	0.00%		9.80%
Other noncontrolling interests	$ 0		$ 5

[1] Derived from audited financial statements.