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Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Changes, Sale of Interest by Parent, Percent

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Equitization of Long-Term Debt For Deficit Held by Noncontrolling Interest

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Sale of Stock, Noncontrolling Interest, Percentage Sold

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Stockholders Equity, Increase From Equity of Noncontrolling Interest

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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The cash outflow associated with the purchase of noncontrolling interest during the period.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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SIGNIFICANT ACCOUNTING POLICIES AND OTHER FINANCIAL DATA - NONCONTROLLING INTERESTS (Details) $ in Millions					1 Months Ended		3 Months Ended	12 Months Ended
	Dec. 02, 2020	Mar. 30, 2020 USD ($)	Feb. 07, 2019	Jan. 01, 2019 USD ($)	Dec. 31, 2020	Feb. 28, 2019 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($)
Noncontrolling Interest [Line Items]
Stock repurchased in the period								$ 566	$ 26	$ 21
Equitization of long-term debt for deficit held by NCI								(22)
Sempra Mexico [Member] \| IEnova [Member]
Noncontrolling Interest [Line Items]
Stock repurchased in the period							$ 9	$ 231	$ 10
Stock repurchased during the period (in shares) \| shares								77,122,780	2,620,000
Sempra Mexico [Member] \| IEnova [Member]
Noncontrolling Interest [Line Items]
Acquired percentage interest	100.00%
Common stock exchange ratio	0.0313
IEnova [Member] \| Sempra Mexico [Member]
Noncontrolling Interest [Line Items]
Ownership interest (as a percent)					70.20%			70.20%	66.60%	66.50%
Ownership percentage held by noncontrolling owners					29.80%			29.80%	33.40%
IEnova [Member] \| Sempra LNG [Member]
Noncontrolling Interest [Line Items]
Ownership percentage sold					16.60%
Ownership percentage after sale					41.70%			41.70%
Bay Gas [Member] \| Sempra LNG [Member]
Noncontrolling Interest [Line Items]
Ownership interest (as a percent)									9.10%
Cash consideration (fair value of total consideration)						$ 20
Bay Gas [Member] \| Sempra LNG [Member]
Noncontrolling Interest [Line Items]
Cash consideration (fair value of total consideration)				$ 20
ICM Ventures Holdings B.V. [Member] \| Sempra Mexico [Member]
Noncontrolling Interest [Line Items]
Ownership interest (as a percent)							82.50%		53.70%
Liberty Gas Storage [Member] \| Sempra LNG [Member]
Noncontrolling Interest [Line Items]
Ownership percentage held by noncontrolling owners		24.60%			0.00%			0.00%	24.60%
LA Storage [Member] \| Liberty Gas Storage, LLC [Member]
Noncontrolling Interest [Line Items]
Ownership percentage held by noncontrolling owners		100.00%
Bay Gas [Member] \| Sempra LNG [Member]
Noncontrolling Interest [Line Items]
Sale of interest (as a percent)			100.00%
Liberty Gas Storage, LLC [Member] \| Sempra LNG [Member]
Noncontrolling Interest [Line Items]
Payments to acquire minority interest		$ 7
Equitization of long-term debt for deficit held by NCI		22
Increase from equity of noncontrolling interest		$ 2
Liberty Gas Storage, LLC [Member] \| Liberty Gas Storage [Member] \| Sempra LNG [Member]
Noncontrolling Interest [Line Items]
Ownership percentage held by noncontrolling owners					100.00%			100.00%