Derivatives and Hedge Accounting Activities (Fair Value of Derivatives) (Detail) - USD ($) $ in Millions		Mar. 31, 2023	Dec. 31, 2022
Derivatives Fair Value [Line Items]
Derivative Asset, Current		$ 264	$ 1,137	[1]
Derivative Asset, Noncurrent	[2]	933	1,039
Derivatives Assets		1,197	2,176
Derivative Liabilities, Current		371	778	[1]
Derivative Liabilities, Noncurrent	[3]	518	626
Derivative Liabilities		889	1,404
Virginia Electric and Power Company
Derivatives Fair Value [Line Items]
Derivative Asset, Current	[4]	91	765	[5]
Derivative Asset, Noncurrent	[2]	142	117
Derivatives Assets		233	882
Derivative Liabilities, Current	[4]	152	298	[5]
Derivative Liabilities, Noncurrent	[3]	184	158
Derivative Liabilities		336	456
Commodity Contract
Derivatives Fair Value [Line Items]
Derivative Asset, Current		157	532
Derivative Asset, Noncurrent		291	237
Derivative Liabilities, Current		309	700
Derivative Liabilities, Noncurrent		84	226
Commodity Contract | Virginia Electric and Power Company
Derivatives Fair Value [Line Items]
Derivative Asset, Current		79	264
Derivative Asset, Noncurrent		63	4
Derivative Liabilities, Current		145	290
Derivative Liabilities, Noncurrent		36	58
Interest Rate Contract
Derivatives Fair Value [Line Items]
Derivative Asset, Current		106	605
Derivative Asset, Noncurrent		642	802
Derivative Liabilities, Current		55	70
Derivative Liabilities, Noncurrent		348	307
Interest Rate Contract | Virginia Electric and Power Company
Derivatives Fair Value [Line Items]
Derivative Asset, Current		11	501
Derivative Asset, Noncurrent		79	113
Derivative Liabilities, Current		0	0
Derivative Liabilities, Noncurrent		62	7
Foreign currency exchange rate
Derivatives Fair Value [Line Items]
Derivative Asset, Current		1
Derivative Liabilities, Current		7	8
Derivative Liabilities, Noncurrent		86	93
Foreign currency exchange rate | Virginia Electric and Power Company
Derivatives Fair Value [Line Items]
Derivative Asset, Current		1
Derivative Liabilities, Current		7	8
Derivative Liabilities, Noncurrent		86	93
Designated as Hedging Instrument
Derivatives Fair Value [Line Items]
Derivative Asset, Current		11	501
Derivative Asset, Noncurrent	[2]	79	113
Derivatives Assets		90	614
Derivative Liabilities, Current		0	0
Derivative Liabilities, Noncurrent	[3]	62	7
Derivative Liabilities		62	7
Designated as Hedging Instrument | Virginia Electric and Power Company
Derivatives Fair Value [Line Items]
Derivative Asset, Current		11	501
Derivative Asset, Noncurrent	[2]	79	113
Derivatives Assets		90	614
Derivative Liabilities, Current		0	0
Derivative Liabilities, Noncurrent	[3]	62	7
Derivative Liabilities		62	7
Designated as Hedging Instrument | Commodity Contract
Derivatives Fair Value [Line Items]
Derivative Asset, Current		0	0
Derivative Asset, Noncurrent		0	0
Derivative Liabilities, Current		0	0
Derivative Liabilities, Noncurrent		0	0
Designated as Hedging Instrument | Commodity Contract | Virginia Electric and Power Company
Derivatives Fair Value [Line Items]
Derivative Asset, Current		0	0
Derivative Asset, Noncurrent		0	0
Derivative Liabilities, Current		0	0
Derivative Liabilities, Noncurrent		0	0
Designated as Hedging Instrument | Interest Rate Contract
Derivatives Fair Value [Line Items]
Derivative Asset, Current		11	501
Derivative Asset, Noncurrent		79	113
Derivative Liabilities, Current		0	0
Derivative Liabilities, Noncurrent		62	7
Designated as Hedging Instrument | Interest Rate Contract | Virginia Electric and Power Company
Derivatives Fair Value [Line Items]
Derivative Asset, Current		11	501
Derivative Asset, Noncurrent		79	113
Derivative Liabilities, Current		0	0
Derivative Liabilities, Noncurrent		62	7
Designated as Hedging Instrument | Foreign currency exchange rate
Derivatives Fair Value [Line Items]
Derivative Asset, Current		0
Derivative Liabilities, Current		0	0
Derivative Liabilities, Noncurrent		0	0
Designated as Hedging Instrument | Foreign currency exchange rate | Virginia Electric and Power Company
Derivatives Fair Value [Line Items]
Derivative Asset, Current		0
Derivative Liabilities, Current		0	0
Derivative Liabilities, Noncurrent		0	0
Fair Value - Derivatives not under Hedge Accounting
Derivatives Fair Value [Line Items]
Derivative Asset, Current		253	636
Derivative Asset, Noncurrent	[2]	854	926
Derivatives Assets		1,107	1,562
Derivative Liabilities, Current		371	778
Derivative Liabilities, Noncurrent	[3]	456	619
Derivative Liabilities		827	1,397
Fair Value - Derivatives not under Hedge Accounting | Virginia Electric and Power Company
Derivatives Fair Value [Line Items]
Derivative Asset, Current		80	264
Derivative Asset, Noncurrent	[2]	63	4
Derivatives Assets		143	268
Derivative Liabilities, Current		152	298
Derivative Liabilities, Noncurrent	[3]	122	151
Derivative Liabilities		274	449
Fair Value - Derivatives not under Hedge Accounting | Commodity Contract
Derivatives Fair Value [Line Items]
Derivative Asset, Current		157	532
Derivative Asset, Noncurrent		291	237
Derivative Liabilities, Current		309	700
Derivative Liabilities, Noncurrent		84	226
Fair Value - Derivatives not under Hedge Accounting | Commodity Contract | Virginia Electric and Power Company
Derivatives Fair Value [Line Items]
Derivative Asset, Current		79	264
Derivative Asset, Noncurrent		63	4
Derivative Liabilities, Current		145	290
Derivative Liabilities, Noncurrent		36	58
Fair Value - Derivatives not under Hedge Accounting | Interest Rate Contract
Derivatives Fair Value [Line Items]
Derivative Asset, Current		95	104
Derivative Asset, Noncurrent		563	689
Derivative Liabilities, Current		55	70
Derivative Liabilities, Noncurrent		286	300
Fair Value - Derivatives not under Hedge Accounting | Interest Rate Contract | Virginia Electric and Power Company
Derivatives Fair Value [Line Items]
Derivative Asset, Current		0	0
Derivative Asset, Noncurrent		0	0
Derivative Liabilities, Current		0	0
Derivative Liabilities, Noncurrent		0	0
Fair Value - Derivatives not under Hedge Accounting | Foreign currency exchange rate
Derivatives Fair Value [Line Items]
Derivative Asset, Current		1
Derivative Liabilities, Current		7	8
Derivative Liabilities, Noncurrent		86	93
Fair Value - Derivatives not under Hedge Accounting | Foreign currency exchange rate | Virginia Electric and Power Company
Derivatives Fair Value [Line Items]
Derivative Asset, Current		1
Derivative Liabilities, Current		7	8
Derivative Liabilities, Noncurrent		$ 86	$ 93

[1] Dominion Energy’s Consolidated Balance Sheet at December 31, 2022 has been derived from the audited Consolidated Balance Sheet at that date.

[2] Noncurrent derivative assets are presented in other deferred charges and other assets in the Companies’ Consolidated Balance Sheets.

[3] Noncurrent derivative liabilities are presented in other deferred credits and other liabilities in the Companies’ Consolidated Balance Sheets.

[4] See Note 19 for amounts attributable to affiliates.

[5] Virginia Power’s Consolidated Balance Sheet at December 31, 2022 has been derived from the audited Consolidated Balance Sheet at that date.