GENERAL INFORMATION AND OTHER FINANCIAL DATA - EARNINGS PER COMMON SHARE (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
(Loss) income from continuing operations, net of income tax	$ (632)	$ 428	$ 751	$ 1,823
Earnings attributable to noncontrolling interests	(5)	(22)	(48)	(191)
Preferred dividends	(11)	(48)	(52)	(121)
Preferred dividends of subsidiary	0	0	(1)	(1)
Earnings from continuing operations attributable to common shares for diluted EPS	(648)	358	650	1,510
(Loss) income from discontinued operations, net of income tax	0	(7)	0	1,850
Earnings attributable to noncontrolling interests	0	0	0	(10)
(Losses) earnings from discontinued operations attributable to Sempra	0	(7)	0	1,840
(Losses) earnings attributable to common shares	$ (648)	$ 351	$ 650	$ 3,350
Weighted-average common shares outstanding for basic EPS	319,144,000	289,490,000	309,350,000	291,771,000
Dilutive effect of stock options and RSUs (in shares)	0	1,092,000	797,000	1,164,000
Dilutive effect of mandatory convertible preferred stock (in shares)	0	0	707,000	0
Weighted-average common shares outstanding for diluted EPS (in shares)	319,144,000	290,582,000	310,854,000	292,935,000
(Losses) earnings from continuing operations (in dollars per share)	$ (2.03)	$ 1.23	$ 2.10	$ 5.17
(Losses) earnings from discontinued operations (in dollars per share)	0	(0.02)	0	6.31
(Losses) earnings (in dollars per share)	(2.03)	1.21	2.10	11.48
(Losses) earnings from continuing operations (in dollars per share)	(2.03)	1.23	2.09	5.15
(Losses) earnings from discontinued operations (in dollars per share)	0	(0.02)	0	6.28
(Losses) earnings (in dollars per share)	$ (2.03)	$ 1.21	$ 2.09	$ 11.43
Vested RSUs included in basic WASO (in shares)	451,000	535,000	453,000	536,000
Performance-based RSUs [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Equity awards, granted (in shares)			323,889
Service-based RSUs [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Equity awards, granted (in shares)			143,980
Stock options, RSAs and RSUs [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Non-qualified stock options granted (in shares)			222,620
Stock Options and Restricted Stock Units
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Antidilutive securities excluded from earnings per share (in shares)	699
Stock options, RSAs and RSUs [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Antidilutive securities excluded from earnings per share (in shares)	147,840	142,100	240,654	204,426
Convertible Preferred Stock Series A [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Antidilutive securities excluded from earnings per share (in shares)	639,733		3,037,812
Convertible Preferred Stock [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Antidilutive securities excluded from earnings per share (in shares)		19,292,641		19,292,641