Accumulated Other Comprehensive Income (Loss) (Schedule of Changes in AOCI Net of Tax and Reclassifications out of AOCI by Component) (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2023		Mar. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	[1]	$ 27,881
Interest and related charges (benefit)		(586)		$ (174)
Other income (expense)		284		46
Income tax expense (benefit)		(221)		(236)
Net Income From Continuing Operations		1,002		692
Total other comprehensive income (loss)		7		22
Ending balance		28,356
Virginia Electric and Power Company
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		17,245	[2]	15,980
Interest and related charges (benefit)	[3]	(181)		(148)
Other income (expense)		36		4
Income before income tax expense		452		418
Income tax expense (benefit)		(99)		(61)
Total other comprehensive income (loss)		(5)		12
Ending balance		17,593		16,348
Total Derivative-Hedging Activities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	[4],[5]	(249)		(358)
Other comprehensive income (loss) before reclassifications: gains (losses)	[4],[5]	(9)		25
Total other comprehensive income (loss)	[4],[5]	(1)		35
Ending balance	[4],[5]	(250)		(323)
Total Derivative-Hedging Activities | Virginia Electric and Power Company
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	[6],[7]	16		(45)
Other comprehensive income (loss) before reclassifications: gains (losses)	[6],[7]	(9)		19
Total other comprehensive income (loss)	[6],[7]	(9)		20
Ending balance	[6],[7]	7		(25)
Total Derivative-Hedging Activities | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest and related charges (benefit)	[4],[5]	11		14
Income before income tax expense	[4],[5]	11		14
Income tax expense (benefit)	[4],[5]	(3)		(4)
Net Income From Continuing Operations	[4],[5]	8		10
Total Derivative-Hedging Activities | Reclassification out of Accumulated Other Comprehensive Income | Virginia Electric and Power Company
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest and related charges (benefit)	[6],[7]			1
Income before income tax expense	[6],[7]			1
Net Income From Continuing Operations	[6],[7]			1
Investment Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	[8]	(44)		37
Other comprehensive income (loss) before reclassifications: gains (losses)	[8]	17		(62)
Total other comprehensive income (loss)	[8]	18		(59)
Ending balance	[8]	(26)		(22)
Investment Securities | Virginia Electric and Power Company
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	[9]	(7)		4
Other comprehensive income (loss) before reclassifications: gains (losses)	[9]	4		(7)
Total other comprehensive income (loss)	[9]	4		(8)
Ending balance	[9]	(3)		(4)
Investment Securities | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other income (expense)	[8]	2		4
Income before income tax expense	[8]	2		4
Income tax expense (benefit)	[8]	(1)		(1)
Net Income From Continuing Operations	[8]	1		3
Investment Securities | Reclassification out of Accumulated Other Comprehensive Income | Virginia Electric and Power Company
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other income (expense)	[9]			(1)
Income before income tax expense	[9]			(1)
Net Income From Continuing Operations	[9]			(1)
Pension and Other Postretirement Benefit Costs
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	[10]	(1,276)		(1,133)
Other comprehensive income (loss) before reclassifications: gains (losses)	[10]			28
Total other comprehensive income (loss)	[10]	(11)		45
Ending balance	[10]	(1,287)		(1,088)
Pension and Other Postretirement Benefit Costs | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other income (expense)	[10]	(15)		23
Income before income tax expense	[10]	(15)		23
Income tax expense (benefit)	[10]	4		(6)
Net Income From Continuing Operations	[10]	(11)		17
Equity Method Investees
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	[11]	(3)		(4)
Other comprehensive income (loss) before reclassifications: gains (losses)	[11]	1		1
Total other comprehensive income (loss)	[11]	1		1
Ending balance	[11]	(2)		(3)
AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		(1,572)		(1,458)
Other comprehensive income (loss) before reclassifications: gains (losses)		9		(8)
Total other comprehensive income (loss)		7		22
Ending balance		(1,565)		(1,436)
AOCI | Virginia Electric and Power Company
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		9		(41)
Other comprehensive income (loss) before reclassifications: gains (losses)		(5)		12
Total other comprehensive income (loss)		(5)		12
Ending balance		4		(29)
AOCI | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest and related charges (benefit)		11		14
Other income (expense)		(13)		27
Income before income tax expense		(2)		41
Income tax expense (benefit)				(11)
Net Income From Continuing Operations		$ (2)		30
AOCI | Reclassification out of Accumulated Other Comprehensive Income | Virginia Electric and Power Company
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest and related charges (benefit)				1
Other income (expense)				$ (1)

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

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

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

[4] Comprised entirely of interest rate derivative hedging activities.

[5] Net of $83 million, $83 million, $107 million and $119 million tax at March 31, 2023, December 31, 2022, March 31, 2022 and December 31, 2021, respectively.

[6] Comprised entirely of interest rate derivative hedging activities.

[7] Net of $(2) million, $(5) million, $9 million and $16 million tax at March 31, 2023, December 31, 2022, March 31, 2022 and December 31, 2021, respectively

[8] Net of $6 million, $13 million, $8 million and $(10) million tax at March 31, 2023, December 31, 2022, March 31, 2022 and December 31, 2021, respectively.

[9] Net of $1 million, $2 million, $1 million and $(2) million tax at March 31, 2023, December 31, 2022, March 31, 2022 and December 31, 2021, respectively.

[10] Net of $449 million, $445 million, $380 million and $396 million tax at March 31, 2023, December 31, 2022, March 31, 2022 and December 31, 2021, respectively.

[11] Net of $— million, $1 million, $1 million and $1 million tax at March 31, 2023, December 31, 2022, March 31, 2022 and December 31, 2021, respectively.