CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Millions	Total		Series A Preferred Stock [Member]	Series B Preferred Stock [Member]	Series C Preferred Stock [Member]	Preferred stock [Member]	Common Stock [Member]	Retained earnings [Member]	Retained earnings [Member] Series A Preferred Stock [Member]	Retained earnings [Member] Series B Preferred Stock [Member]	Retained earnings [Member] Series C Preferred Stock [Member]	Accumulated other comprehensive income (loss) [Member]	Shareholders' equity [Member]	Shareholders' equity [Member] Series A Preferred Stock [Member]	Shareholders' equity [Member] Series B Preferred Stock [Member]	Shareholders' equity [Member] Series C Preferred Stock [Member]	Noncontrolling Interest [Member]	San Diego Gas and Electric Company [Member]	San Diego Gas and Electric Company [Member] Common Stock [Member]	San Diego Gas and Electric Company [Member] Retained earnings [Member]	San Diego Gas and Electric Company [Member] Accumulated other comprehensive income (loss) [Member]	San Diego Gas and Electric Company [Member] Shareholders' equity [Member]	San Diego Gas and Electric Company [Member] Noncontrolling Interest [Member]	Southern California Gas Company [Member]	Southern California Gas Company [Member] Preferred stock [Member]	Southern California Gas Company [Member] Common Stock [Member]	Southern California Gas Company [Member] Retained earnings [Member]	Southern California Gas Company [Member] Accumulated other comprehensive income (loss) [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] Retained earnings [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] Accumulated other comprehensive income (loss) [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] Shareholders' equity [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] Noncontrolling Interest [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] San Diego Gas and Electric Company [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] San Diego Gas and Electric Company [Member] Retained earnings [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] San Diego Gas and Electric Company [Member] Accumulated other comprehensive income (loss) [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] Southern California Gas Company [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] Southern California Gas Company [Member] Retained earnings [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] Southern California Gas Company [Member] Accumulated other comprehensive income (loss) [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Preferred stock [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Common Stock [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Retained earnings [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Accumulated other comprehensive income (loss) [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Shareholders' equity [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Noncontrolling Interest [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] San Diego Gas and Electric Company [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] San Diego Gas and Electric Company [Member] Common Stock [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] San Diego Gas and Electric Company [Member] Retained earnings [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] San Diego Gas and Electric Company [Member] Accumulated other comprehensive income (loss) [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] San Diego Gas and Electric Company [Member] Shareholders' equity [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] San Diego Gas and Electric Company [Member] Noncontrolling Interest [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Southern California Gas Company [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Southern California Gas Company [Member] Preferred stock [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Southern California Gas Company [Member] Common Stock [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Southern California Gas Company [Member] Retained earnings [Member]	Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Southern California Gas Company [Member] Accumulated other comprehensive income (loss) [Member]
Beginning Balance at Dec. 31, 2018	$ 19,248					$ 2,258	$ 5,540	$ 10,104				$ (764)	$ 17,138				$ 2,110	$ 6,115	$ 1,338	$ 4,687	$ (10)	$ 6,015	$ 100	$ 4,258	$ 22	$ 866	$ 3,390	$ (20)						$ 0	$ 2	$ (2)	$ (2)	$ 2	$ (4)	$ 19,263	$ 2,258	$ 5,540	$ 10,161	$ (806)	$ 17,153	$ 2,110	$ 6,115	$ 1,338	$ 4,689	$ (12)	$ 6,015	$ 100	$ 4,256	$ 22	$ 866	$ 3,392	$ (24)
Beginning Balance (Accounting Standards Update 2016-02 [Member]) at Dec. 31, 2018																													$ 17	$ 17		$ 17
Beginning Balance (Accounting Standards Update 2018-02 [Member]) at Dec. 31, 2018																													(2)	40	$ (42)	(2)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	1,862							1,716					1,716				146	589		582		582	7	438			438
Other comprehensive (loss) income	(190)											(172)	(172)				(18)	3			1	1	2	5				5
Equity contribution from Sempra Energy																		322	322			322
Share-based compensation expense	56						56						56
Dividends declared:
Preferred dividends			$ (78)	$ (29)					$ (78)	$ (29)				$ (78)	$ (29)									(1)			(1)
Common stock dividends declared	(803)							(803)					(803)											(150)			(150)
Preferred dividends of subsidiary	(1)							(1)					(1)
Issuances of stock	798						798						798
Repurchases of common stock	(23)						(23)						(23)
Noncontrolling interest activities:
Contributions	175																175	175					175
Distributions	(17)						2						2				(19)	(3)					(3)
Purchases	(30)						(3)						(3)				(27)
Sale	5						4						4				1
Acquisition	3																3
Deconsolidation	(440)																(440)	(281)					(281)
Ending balance at Sep. 30, 2019	$ 20,551					2,258	6,374	10,966				(978)	18,620				1,931	6,920	1,660	5,271	(11)	6,920	0	$ 4,548	22	866	3,679	(19)
Noncontrolling interest activities:
Dividends declared per share of common stock (in dollars per share)	$ 2.90																							$ 1.64
Beginning Balance at Jun. 30, 2019	$ 19,434					2,258	5,605	10,425				(848)	17,440				1,994	6,438	1,338	5,008	(11)	6,335	103	$ 4,554	22	866	3,686	(20)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	909							849					849				60	266		263		263	3	143			143
Other comprehensive (loss) income	(142)											(130)	(130)				(12)	1					1	1				1
Equity contribution from Sempra Energy																		322	322			322
Share-based compensation expense	17						17						17
Dividends declared:
Preferred dividends			(26)	(10)					(26)	(10)				(26)	(10)									0			0
Common stock dividends declared	(272)							(272)					(272)											(150)			(150)
Issuances of stock	751						751						751
Repurchases of common stock	(5)						(5)						(5)
Noncontrolling interest activities:
Contributions	175																175	175					175
Distributions	(5)						2						2				(7)	(1)					(1)
Purchases	(2)																(2)
Sale	5						4						4				1
Acquisition	3																3
Deconsolidation	(281)																(281)	(281)					(281)
Ending balance at Sep. 30, 2019	$ 20,551					2,258	6,374	10,966				(978)	18,620				1,931	6,920	1,660	5,271	(11)	6,920	0	$ 4,548	22	866	3,679	(19)
Noncontrolling interest activities:
Dividends declared per share of common stock (in dollars per share)	$ 0.96																							$ 1.64
Beginning Balance at Dec. 31, 2019	$ 21,805	[1]				2,258	7,480	11,130				(939)	19,929				1,876	7,100	1,660	5,456	(16)	7,100	0	$ 4,748	22	866	3,883	(23)	$ (9)	$ (7)		$ (7)	$ (2)							$ 21,796	$ 2,258	$ 7,480	$ 11,123	$ (939)	$ 19,922	$ 1,874
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	3,673							3,472					3,472				201	633		633		633	0	426			426
Other comprehensive (loss) income	406											431	431				(25)	4			4	4	0	1				1
Share-based compensation expense	57						57						57
Dividends declared:
Preferred dividends			(78)	(29)	$ (14)				(78)	(29)	$ (14)			(78)	(29)	$ (14)								(1)			(1)
Common stock dividends declared	(913)							(913)					(913)					(200)		(200)		(200)		(100)			(100)
Preferred dividends of subsidiary	(1)							(1)					(1)
Issuance of series C preferred stock	889					889							889
Issuances of stock	33						33						33
Repurchases of common stock	(565)						(565)						(565)
Noncontrolling interest activities:
Distributions	(1)																(1)
Purchases	(184)						29					(5)	24				(208)
Acquisition	1																1
Equitization of long-term debt for deficit held by NCI	22																22
Deconsolidation	(236)																(236)
Ending balance at Sep. 30, 2020	$ 24,856					3,147	7,034	13,560				(513)	23,228				1,628	$ 7,537	1,660	5,889	(12)	7,537	0	$ 5,074	22	866	4,208	(22)
Noncontrolling interest activities:
Dividends declared per share of common stock (in dollars per share)	$ 3.14																	$ 1.72						$ 1.10
Beginning Balance at Jun. 30, 2020	$ 25,386					3,147	7,490	13,511				(542)	23,606				1,780	$ 7,359	1,660	5,711	(12)	7,359	0	$ 5,148	22	866	4,282	(22)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	421							399					399				22	178		178		178	0	(24)			(24)
Other comprehensive (loss) income	38											34	34				4
Share-based compensation expense	19						19						19
Dividends declared:
Preferred dividends			$ (26)	$ (10)	$ (12)				$ (26)	$ (10)	$ (12)			$ (26)	$ (10)	$ (12)								0			0
Common stock dividends declared	(302)							(302)					(302)											(50)			(50)
Repurchases of common stock	(501)						(501)						(501)
Noncontrolling interest activities:
Purchases	(157)						26					(5)	21				(178)
Ending balance at Sep. 30, 2020	$ 24,856					$ 3,147	$ 7,034	$ 13,560				$ (513)	$ 23,228				$ 1,628	$ 7,537	$ 1,660	$ 5,889	$ (12)	$ 7,537	$ 0	$ 5,074	$ 22	$ 866	$ 4,208	$ (22)
Noncontrolling interest activities:
Dividends declared per share of common stock (in dollars per share)	$ 1.05																							$ 0.55

[1] Derived from audited financial statements.