GENERAL INFORMATION AND OTHER FINANCIAL DATA - SHAREHOLDER'S EQUITY AND NONCONTROLLING INTEREST (Details) $ / shares in Units, $ / shares in Units, $ in Billions							1 Months Ended						3 Months Ended			9 Months Ended
	Nov. 01, 2021 USD ($)	Oct. 01, 2021 USD ($)	Apr. 04, 2021 USD ($)	Aug. 04, 2020 $ / shares shares	Jul. 01, 2020 USD ($)	Jun. 19, 2020 USD ($) $ / shares shares	Oct. 31, 2021 USD ($)	Sep. 30, 2021 USD ($) class $ / shares shares	Sep. 30, 2021 MXN ($) class $ / shares shares	Jul. 31, 2021 USD ($)	May 31, 2021 USD ($) shares	Mar. 31, 2020 USD ($)	Sep. 30, 2021 USD ($) class shares	Sep. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Sep. 30, 2021 USD ($) class shares	Sep. 30, 2020 USD ($) shares	Jul. 15, 2021 shares	Jul. 06, 2021	Apr. 30, 2021	Jan. 15, 2021 shares	Jul. 06, 2020 USD ($) shares	Mar. 30, 2020	Dec. 31, 2019	Sep. 11, 2007 USD ($) shares
Subsidiary, Sale of Stock [Line Items]
Shares issued (in shares) | shares											12,306,777
Repurchases of common stock													$ 1,000,000	$ 501,000,000		$ 39,000,000	$ 565,000,000
Equitization of long-term debt for deficit held by NCI																	22,000,000
Income Tax Expense (Benefit)													$ (342,000,000)	$ 99,000,000		$ (45,000,000)	$ 60,000,000
Limited Partnership distributions (as a percent)			85.00%
Number of authorized classes of units | class								2	2				2			2
Limited Partnership Agreement, Ownership Percentage								80.00%	80.00%				80.00%			80.00%
Common Stock [Member]
Subsidiary, Sale of Stock [Line Items]
Stock repurchase program, authorized amount																						$ 2,000,000,000			$ 2,000,000,000
Stock repurchase program, authorized number of shares (in shares) | shares								0	0				0			0						25,000,000			40,000,000
Accelerated share repurchase program, prepaid amount					$ 500,000,000
Share repurchase program, number of shares repurchased (in shares) | shares				4,089,375
Common stock repurchased, average price (in dollars per share) | $ / shares				$ 122.27
Series B Preferred Stock [Member]
Subsidiary, Sale of Stock [Line Items]
Shares converted | shares																		5,750,000
Convertible Preferred Stock Series B [Member]
Subsidiary, Sale of Stock [Line Items]
Shares converted | shares																		4,256,720
Preferred stock, conversion ratio																		0.7403
Series A Preferred Stock [Member]
Subsidiary, Sale of Stock [Line Items]
Shares converted | shares																					17,250,000
Convertible Preferred Stock Series A [Member]
Subsidiary, Sale of Stock [Line Items]
Shares converted | shares																					13,781,025
Preferred stock, conversion ratio																					0.7989
Series C Preferred Stock [Member]
Subsidiary, Sale of Stock [Line Items]
Preferred stock, shares issued (in shares) | shares						900,000
Preferred stock, redemption price per share (in dollars per share) | $ / shares						$ 1,000
Proceeds from issuance of preferred stock						$ 889,000,000
Preferred stock, discount						$ 11,000,000
Debt Instrument, Interest Rate, Stated Percentage						4.875%
Forecast [Member]
Subsidiary, Sale of Stock [Line Items]
Direct and indirect net debt at closing		$ 8,370,000,000
Subsequent Event [Member] | KKR [Member]
Subsidiary, Sale of Stock [Line Items]
Disbursements to be paid	$ 300,000,000
Repayment of disbursements, rate (as a percent)	5.00%
Infraestructura Energética Nova [Member]
Subsidiary, Sale of Stock [Line Items]
Common stock acquired (in shares) | shares								51,014,545	51,014,545		381,015,194
Common stock exchange ratio											0.0323
Value of shares acquired								$ 202,000,000	$ 4.0
Common Shares Repurchased, Share Price | (per share)								$ 3.95	$ 78.97
Increase in stockholders' equity								$ 84,000,000
Infraestructura Energética Nova [Member] | Subsequent Event [Member]
Subsidiary, Sale of Stock [Line Items]
Income Tax Expense (Benefit)							$ 72,000,000
Sempra Energy [Member] | Series B Preferred Stock [Member]
Subsidiary, Sale of Stock [Line Items]
Percentage of common shares held (as a percent)																			1.00%
LA Storage [Member] | Liberty Gas Storage, LLC [Member]
Subsidiary, Sale of Stock [Line Items]
Ownership percentage												100.00%			100.00%
IEnova [Member]
Subsidiary, Sale of Stock [Line Items]
Purchase price of equity interests								14,000,000			$ 1,361,000,000
Transaction costs								$ 1,000,000			$ 12,000,000
Ownership interest (as a percent)								99.90%	99.90%		96.40%		99.90%			99.90%				70.20%
Noncontrolling Interest, Remaining Shares Of Noncontrolling Interest | shares								1,212,981	1,212,981				1,212,981			1,212,981
IEnova [Member] | Subsequent Event [Member]
Subsidiary, Sale of Stock [Line Items]
Ownership interest (as a percent)		99.90%
Sempra Global | KKR [Member]
Subsidiary, Sale of Stock [Line Items]
Purchase price of equity interests			$ 3,370,000,000
Sempra Global | Subsequent Event [Member] | KKR [Member]
Subsidiary, Sale of Stock [Line Items]
Noncontrolling Interest, Payment For Reimbursement of Expenses		$ 149,000,000
Sale of Noncontrolling Interest, Downward Price Adjustment		$ 1,000,000
Sempra Global | KKR [Member]
Subsidiary, Sale of Stock [Line Items]
Ownership percentage			20.00%
Liberty Gas Storage, LLC [Member] | Sempra LNG [Member]
Subsidiary, Sale of Stock [Line Items]
Payment to acquire remaining interest												$ 7,000,000
Equitization of long-term debt for deficit held by NCI												22,000,000
Increase from equity of noncontrolling interest												$ 2,000,000
Sempra Mexico [Member] | ICM Ventures Holdings B.V. [Member]
Subsidiary, Sale of Stock [Line Items]
Additional ownership percentage																			17.50%
Sempra Mexico [Member] | Infraestructura Energética Nova [Member]
Subsidiary, Sale of Stock [Line Items]
Common stock repurchased (in shares) | shares																	57,547,381
Repurchases of common stock																	$ 167,000,000
Sempra Mexico [Member] | ICM Ventures Holdings B.V. [Member]
Subsidiary, Sale of Stock [Line Items]
Ownership interest (as a percent)												82.50%			82.50%									53.70%
Payment to acquire remaining interest										$ 7,000,000					$ 9,000,000
Sempra Mexico [Member] | IEnova [Member]
Subsidiary, Sale of Stock [Line Items]
Ownership interest (as a percent)														69.20%			69.20%							66.60%
Sempra LNG [Member] | Liberty Gas Storage, LLC [Member]
Subsidiary, Sale of Stock [Line Items]
Ownership percentage																							24.60%
Sempra LNG [Member] | Liberty Gas Storage, LLC [Member] | Liberty Gas Storage, LLC [Member]
Subsidiary, Sale of Stock [Line Items]
Ownership percentage												100.00%			100.00%