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, 2025		Mar. 31, 2024
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	[1]	$ 27,253
Total other comprehensive income (loss)		4		$ (7)
Ending balance		27,365
Virginia Electric and Power Company
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	[2]	22,214
Total other comprehensive income (loss)		(5)		3
Ending balance		22,692
Total Derivative-Hedging Activities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	[3],[4]	(171)		(216)
Other comprehensive income (loss) before reclassifications: gains (losses)	[3],[4]	(16)		7
Income tax expense (benefit)	[3],[4]	(2)		(4)
Total, net of tax	[3],[4]	8		7
Total other comprehensive income (loss)	[3],[4]	(8)		14
Ending balance	[3],[4]	(179)		(202)
Total Derivative-Hedging Activities | Virginia Electric and Power Company
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	[5],[6]	28		15
Other comprehensive income (loss) before reclassifications: gains (losses)	[5],[6]	(7)		7
Income tax expense (benefit)	[6]	0	[3]	0	[5]
Total, net of tax	[6]	0	[3]	0	[5]
Total other comprehensive income (loss)	[5],[6]	(7)		7
Ending balance	[5],[6]	21		22
Total Derivative-Hedging Activities | Amounts reclassified from AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest and related charges (benefit)	[3],[4]	10		11
Income (loss) before income tax expense	[3],[4]	10		11
Total Derivative-Hedging Activities | Amounts reclassified from AOCI | Virginia Electric and Power Company
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other income (expense)	[5],[6]			0
Income (loss) before income tax expense	[6]	0	[5]	0	[3]
Investment Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	[7]	(14)		0
Other comprehensive income (loss) before reclassifications: gains (losses)	[7]	13		(26)
Income tax expense (benefit)	[7]	0		(2)
Total, net of tax	[7]	2		6
Total other comprehensive income (loss)	[7]	15		(20)
Ending balance	[7]	1		(20)
Investment Securities | Virginia Electric and Power Company
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	[8]	(1)		1
Other comprehensive income (loss) before reclassifications: gains (losses)	[8]	2		(5)
Income tax expense (benefit)	[8]	0		(1)
Total, net of tax	[8]	0		1
Total other comprehensive income (loss)	[8]	2		(4)
Ending balance	[8]	1		(3)
Investment Securities | Amounts reclassified from AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other income (expense)	[7]	2		8
Income (loss) before income tax expense	[7]	2		8
Investment Securities | Amounts reclassified from AOCI | Virginia Electric and Power Company
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other income (expense)	[8]	0		2
Income (loss) before income tax expense	[8]	0		2
Pension and Other Postretirement Benefit Costs
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	[9],[10]	29		43
Other comprehensive income (loss) before reclassifications: gains (losses)	[9],[10]	0		0
Income tax expense (benefit)	[9],[10]	0		3
Total, net of tax	[9],[10]	(3)		(1)
Total other comprehensive income (loss)	[9],[10]	(3)		(1)
Ending balance	[9],[10]	26		42
Pension and Other Postretirement Benefit Costs | Amounts reclassified from AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other income (expense)	[9],[10]	(3)		(4)
Income (loss) before income tax expense	[9],[10]	(3)		(4)
AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		(156)		(173)
Other comprehensive income (loss) before reclassifications: gains (losses)		(3)		(19)
Income tax expense (benefit)		(2)		(3)
Total, net of tax		7		12
Total other comprehensive income (loss)		4		(7)
Ending balance		(152)		(180)
AOCI | Virginia Electric and Power Company
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		27		16
Other comprehensive income (loss) before reclassifications: gains (losses)		(5)		2
Income tax expense (benefit)		0		(1)
Total, net of tax		0		1
Total other comprehensive income (loss)		(5)		3
Ending balance		22		19
AOCI | Amounts reclassified from AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest and related charges (benefit)		10		11
Other income (expense)		(1)		4
Income (loss) before income tax expense		9		15
AOCI | Amounts reclassified from AOCI | Virginia Electric and Power Company
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other income (expense)		0		2
Income (loss) before income tax expense		$ 0		$ 2

[1] Dominion Energy’s Consolidated Balance Sheet at December 31, 2024 has been derived from the audited Consolidated Balance Sheet at that date.

[2] Virginia Power’s Consolidated Balance Sheet at December 31, 2024 has been derived from the audited Consolidated Balance Sheet at that date.

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

[4] Net of $61 million, $58 million, $68 million and $73 million tax at March 31, 2025, December 31, 2024, March 31, 2024 and December 31, 2023, respectively.

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

[6] Net of $(7) million, $(10) million, $(7) million and $(5) million tax at March 31, 2025, December 31, 2024, March 31, 2024 and December 31, 2023, respectively.

[7] Net of $— million, $5 million, $6 million and $(2) million tax at March 31, 2025, December 31, 2024, March 31, 2024 and December 31, 2023, respectively.

[8] Net of $— million, $— million, $1 million and $— million tax at March 31, 2025, December 31, 2024, March 31, 2024 and December 31, 2023, respectively.

[9] Comprised entirely of prior service cost.

[10] Net of $(9) million, $(9) million, $(10) million and $(14) million tax at March 31, 2025, December 31, 2024, March 31, 2024 and December 31, 2023, respectively.