GENERAL INFORMATION AND OTHER FINANCIAL DATA - OTHER NONCONTROLLING INTERESTS (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Noncontrolling Interest [Line Items]
Other noncontrolling interests	$ 30	$ 1,541	[1]
IEnova [Member] | Sempra Mexico [Member]
Noncontrolling Interest [Line Items]
Ownership percentage	0.10%	29.80%
Other noncontrolling interests	$ 2	$ 1,487
IEnova subsidiaries [Member] | Sempra Mexico [Member]
Noncontrolling Interest [Line Items]
Ownership percentage	0.00%	17.50%
Other noncontrolling interests	$ 0	$ 7
ECA LNG Proposed Liquefaction Project [Member] | Sempra LNG [Member]
Noncontrolling Interest [Line Items]
Ownership percentage	16.60%	29.00%
Other noncontrolling interests	$ 28	$ 46
PXISE Energy Solutions LLC [Member] | Parent and Other [Member]
Noncontrolling Interest [Line Items]
Ownership percentage	20.00%	20.00%
Other noncontrolling interests	$ 0	$ 1

[1] Derived from audited financial statements.